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Fungi, which are widely distributed across the Earth, have successfully managed to colonize cold environments (e.g., polar regions, alpine ecosystems, and glaciers) despite the challenging conditions for life. They are capable of living in extremely harsh environments due to their ecological versatility and morphological plasticity. It is also believed that lower eukaryotes are the most adapted to life at low temperatures among microorganisms that thrive in cold environments. They play important ecological roles, contributing to nutrient recycling and organic matter mineralization. These highly specialized microorganisms have developed adaptation strategies to overcome the direct and indirect harmful influences of low temperatures. They have evolved a wide range of complex and cooperative adaptations at various cellular levels, including modifications to the cell envelope and enzymes, the production of cryoprotectants and chaperones, and the development of new metabolic functions. Adaptation to cold environments has made fungi an exciting source for the discovery of new cold-adapted enzymes (e.g., proteinases, lipases) and secondary metabolites (e.g., pigments, osmolytes, polyunsaturated fatty acids) for widespread use in biotechnology, food technology, agriculture, pharmaceutics, molecular biology, textile industry, and environmental bioremediation in cold climates. This review aims to provide a comprehensive overview of the adaptive strategies employed by psychrophilic yeasts and fungi, highlighting their ecological roles and biotechnological potential. Understanding these adaptive mechanisms not only sheds light on microbial life in extreme environments but also paves the way for innovative applications in the food industry and agriculture. [ABSTRACT FROM AUTHOR]

Bees play important roles in socio-economic development, biodiversity conservation, and ecosystem stability. However, during the cold season, resources become limited, leading to significant losses in bee colonies. Although many studies have described the characteristics of winter bees and demonstrated that notable changes occur in their gut microflora, the underlying mechanisms remain yet to be fully elucidated. Therefore, this study was conducted to compare the gut microbiota dynamics of overwintering bees. Sample acquisition involved randomly selecting ten colonies each from three bee farms containing Apis cerana (AC) and Apis mellifera (AM), followed by dissection for further analysis. DNA was extracted, and 16S rDNA sequencing, along with various bioinformatics tools, was used to assess microbial diversity, functional differences, and species comparisons between AC and AM gut microbiota. AC exhibited lower β diversity in the gut microbiota than AM during winter. Moreover, Gilliamella and Apibacter were relatively more abundant in AC. Regarding microbial functions, key pathways included the phosphotransferase system, galactose metabolism, the pentose phosphate pathway, and carbohydrate transport and metabolism. These results suggest the presence of microbial diversity differences between AC and AM, with the differential microbial functions mainly enriched in metabolic pathways that facilitate adaptation to cold environmental stress. [ABSTRACT FROM AUTHOR]

Separation of duplex strands of nucleic acids is a vital process in the nucleic acid metabolism and survival of all living organisms. Helicases are defined as enzymes that are intended to unwind the double-stranded nucleic acids. Helicases play a prominent role in the cold adaptation of plants and bacteria. Cold stress can increase double-strand DNA breaks, generate reactive oxygen species, cause DNA methylation, and stabilize the secondary structure of RNA molecules. In this review, we discuss how helicases play important roles in adaptive responses to cellular stress caused by low temperature conditions, particularly in bacteria and plants. We also provide a glimpse of the eminence of helicase function over nuclease when an enzyme has both helicase and nuclease functions. [ABSTRACT FROM AUTHOR]

Simple Summary: This study examined the transcriptome and physiological responses of cold-tolerant soybean cultivar "KD52" and cold-sensitive cultivar "DS17". Increased malondialdehyde levels demonstrated DS17's vulnerability to lipid peroxidation and membrane breakdown. In contrast, cold exposure boosted antioxidant enzyme activity in the KD52 cultivar, including peroxidase and superoxide dismutase, demonstrating a strong antioxidant defense system against oxidative stress. A transcriptomic study mapped 54,532 genes and showed dynamic responses. This group had 234 differentially expressed genes (DEGs) that consistently changed over time, indicating unique expression patterns in the 2 cultivars. These key DEGs and physiological markers were linked to candidate genes for oxidative damage management and antioxidant defenses. The identification of improved defense mechanisms in KD52 and key genes should improve soybean cold stress tolerance. Low temperatures greatly restrict the development, growth, and productivity of soybeans, with their effects differing across various cultivars. The present work investigated the transcriptome and physiological reactions of two soybean cultivars, namely "KD52" exhibiting cold tolerance and "DS17" displaying cold sensitivity, to cold stress across a precisely defined period. The soybean plants were subjected to cold treatment at 6 °C for durations of 0, 2, 4, and 8 h. A comparative physiological marker study revealed distinct reactions to cold stress in the two cultivars. The findings showed that increased malondialdehyde levels provided evidence of DS17's heightened vulnerability to lipid peroxidation and membrane degradation. In contrast, the KD52 cultivar exhibited increased activities of antioxidant enzymes, including peroxidase and superoxide dismutase, in response to cold exposure, suggesting a strong antioxidant defense system against oxidative stress. The transcriptomic analysis revealed dynamic responses, mapping 54,532 genes. Within this group, a total of 234 differentially expressed genes (DEGs) were found to be consistently changed at several time intervals, showing unique expression patterns across the two cultivars. Analysis of the association between these important DEGs and the physiological indicators revealed candidate genes that may be involved in controlling oxidative damage and antioxidant defenses. Some key genes showed a progressive rise in expression over time in both cultivars, with a more significant acceleration in KD52, and are probably involved in promoting adaptation processes during extended periods of cold exposure. The identification of improved defense mechanisms in KD52, together with the identification of crucial genes, offers great prospects for enhancing the cold stress resilience of soybean. [ABSTRACT FROM AUTHOR]

In the present review, we summarize genome mining of genomic data obtained from the psychrophilic Antarctic marine ciliate Euplotes focardii and its evolutionary-close mesophilic cosmopolitan counterpart E. crassus. This analysis highlights adaptation strategies that are unique to the Antarctic ciliate, including antioxidant gene duplication and distinctive substitutions that may play roles in increased drug binding affinity and enzyme reaction rate in cold environments. Enzymes from psychrophiles are usually characterized by high activities and reaction rates at low temperatures compared with their counterparts from mesophiles and thermophiles. As a rule, catalyst cold activity derives from an increased structural flexibility that may lead to protein denaturation in response to temperature fluctuation. Molecular thermolability has been a major drawback of using macromolecules from psychrophiles in industrial applications. Here, we report a case study in which the role of peculiar amino acid substitution in cold adaptation is demonstrated by site-directed mutagenesis. Combined with a rational design approach, these substitutions can be used for site-directed mutagenesis to obtain cold-active catalysts that are structurally stable. Furthermore, molecular docking analysis of β-tubulin isotypes extrapolated from E. focardii and E. crassus genomes allowed us to obtain additional insight on the taxol binding site and drug affinity. E. focardii genome mining and the comparison with the mesophilic sibling counterpart can be used as an inspiration for molecular engineering for medical and industrial applications. [ABSTRACT FROM AUTHOR]

Background. In many studies over the past decade, scientists have made a connection between the composition of gut microbiota and human health. A number of publications have shown that gut bacteria are involved in many metabolic and physiological processes of the organism. The composition of the gut microbiome is unique for each person and is formed under the influence of various factors associated with both the individual characteristics of the body and the characteristics of the environment. Different regional characteristics make it necessary for the body to adapt to certain conditions, including temperature fluctuations. Living in areas with low temperatures, such as the Arctic zone, dictates the need for increased energy consumption, which affects the composition of the gut microbiome. Methods. In our study, an extensive questionnaire was conducted among the participants, where many questions were included about the dietary preferences of the study participants, which allowed them us to further divide them into groups according to their diets. Stool samples were collected from participants from 3 groups: Arctic native, Arctic newcomer and the control group. The next step was the isolation of bacterial DNA and sequencing the 16S rRNA gene. The analysis of the results of the diversity of the intestinal microbiota was carried out both with and without taking into account the dietary preferences of the participants. Results. As a result of comparing the intestinal microbiota obtained from residents of the Arctic zone with the gut microbiota of residents of other regions with a milder climate, significant differences are found. These differences may be related to limited food resources and a reduction in the variety of food products characteristic of this Arctic region. t was also found that representatives of the bacterial families Christensenellaceae and Muribaculaceae dominated the control group, both with traditional nutrition and with a dairy-free diet in comparison with the Arctic groups. The control group was dominated by representatives of the Prevotellaceae, Enterobacteriaceae and Comamonadaceae families compared to the Arctic group (with a traditional diet). The results also show that the number of representatives of the families Desulfovibrionaceae (with traditional diet) and Enterobacteriaceae (with milk-free diet) is growing in the Arctic group. Conclusions. In the course of this work, bacterial families characteristic of people living in the Arc-tic zone of the Far Eastern region of the Russian Federation were identified. Poor diet, difficult climatic conditions, and problems with logistics and medical care can have a strong impact on the health of this population. The main type of diet for the inhabitants of the Arctic is the traditional type of diet. They consume a large number of low-cost products, obtainget animal protein from poultry and canned food, and also eat a small number of fresh vegetables and fruits. Such a diet is due to the social status of the study participants and the climatic and geographical features of the region (difficulties in agriculture). With such a diet, we observe a decrease in representatives of the Christensenellaceae, Muribaculaceae, Eubacteriaceae, and Prevotellaceae families and an increase in representatives of the Enterobacteriaceae and Desulfovibrionaceae families among Arctic residents. This imbalance in the futuremay cause, this population may to develop various diseases in the future, including chronic diseases such as obesity, intestinal dysbiosis, inflammatory bowel diseases, and type 2 diabetes. [ABSTRACT FROM AUTHOR]

Russian Snow White (RSW) chickens are characterized by high egg production, extreme resistance to low temperatures, disease resistance, and by the snow-white color of the day-old chicks. Studying the genome of this unique chicken breed will reveal its evolutionary history and help to understand the molecular genetic mechanisms underlying the unique characteristics of this breed, which will open new breeding opportunities and support future studies. We have sequenced and made a de novo assembly of the whole RSW genome using deep sequencing (250×) by the short reads. The genome consists of 40 chromosomes with a total length of 1.1 billion nucleotide pairs. Phylogenetic analysis placed the RSW near the White Leghorn, Fayoumi, and Houdan breeds. Comparison with other chicken breeds revealed a wide pool of mutations unique to the RSW. The functional annotation of these mutations showed the adaptation of genes associated with the development of the nervous system, thermoreceptors, purine receptors, and the TGF-beta pathway, probably caused by selection for low temperatures. We also found adaptation of the immune system genes, likely driven by selection for resistance to viral diseases. Integration with previous genome-wide association studies (GWAS) suggested several causal single nucleotide polymorphisms (SNPs). Specifically, we identified an RSW-specific missense mutation in the RALYL gene, presumably causing the snow-white color of the day-old chicks, and an RSW-specific missense mutation in the TLL1 gene, presumably affecting the egg weight. [ABSTRACT FROM AUTHOR]

The article discusses the growing concern over the effects of heat on human health and the need to quantify and describe the thermal environment. It emphasizes the complexity of understanding the impact of thermal stimuli on humans and the necessity of considering multiple variables. The article highlights the importance of using appropriate thermal indices to evaluate the effects of the thermal environment on humans and identifies five indices that are suitable for biometeorological evaluation. It also emphasizes the need for interdisciplinary communication and the importance of considering cultural and social factors in thermal assessments. The article concludes by emphasizing the importance of using the appropriate thermal index for specific locations and climates and the need for effective communication methods when working with non-experts. [Extracted from the article]

Recently, prokaryotic laccases from lactic acid bacteria (LAB), which can degrade biogenic amines, were discovered. A laccase enzyme has been cloned from Oenococcus oeni, a very important LAB in winemaking, and it has been expressed in Escherichia coli. This enzyme has similar characteristics to those previously isolated from LAB as the ability to oxidize canonical substrates such as 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,6-dimethoxyphenol (2,6-DMP), and potassium ferrocyanide K4[Fe(CN6)], and non-conventional substrates as biogenic amines. However, it presents some distinctiveness, the most characteristic being its psychrophilic behaviour, not seen before among these enzymes. Psychrophilic enzymes capable of efficient catalysis at low temperatures are of great interest due to their potential applications in various biotechnological processes. In this study, we report the discovery and characterization of a new psychrophilic laccase, a multicopper oxidase (MCO), from the bacterium Oenococcus oeni. The psychrophilic laccase gene, designated as LcOe 229, was identified through the genomic analysis of O. oeni, a Gram-positive bacterium commonly found in wine fermentation. The gene was successfully cloned and heterologously expressed in Escherichia coli, and the recombinant enzyme was purified to homogeneity. Biochemical characterization of the psychrophilic laccase revealed its optimal activity at low temperatures, with a peak at 10 °C. To our knowledge, this is the lowest optimum temperature described so far for laccases. Furthermore, the psychrophilic laccase demonstrated remarkable stability and activity at low pH (optimum pH 2.5 for ABTS), suggesting its potential for diverse biotechnological applications. The kinetic properties of LcOe 229 were determined, revealing a high catalytic efficiency (kcat/Km) for several substrates at low temperatures. This exceptional cold adaptation of LcOe 229 indicates its potential as a biocatalyst in cold environments or applications requiring low-temperature processes. The crystal structure of the psychrophilic laccase was determined using X-ray crystallography demonstrating structural features similar to other LAB laccases, such as an extended N-terminal and an extended C-terminal end, with the latter containing a disulphide bond. Also, the structure shows two Met residues at the entrance of the T1Cu site, common in LAB laccases, which we suggest could be involved in substrate binding, thus expanding the substrate-binding pocket for laccases. A structural comparison of LcOe 229 with Antarctic laccases has not revealed specific features assigned to cold-active laccases versus mesophilic. Thus, further investigation of this psychrophilic laccase and its engineering could lead to enhanced cold-active enzymes with improved properties for future biotechnological applications. Overall, the discovery of this novel psychrophilic laccase from O. oeni expands our understanding of cold-adapted enzymes and presents new opportunities for their industrial applications in cold environments. [ABSTRACT FROM AUTHOR]

Investigations and research on the giant African snail (GAS) mainly focus on Achatina fulica. However, in recent years, a more harmful GAS, Achatina immaculata, has been reported. In order to understand the invasive status of A. immaculata in China, we take Shenzhen, a coastal city in Southern China, as an example to carry out an ecological survey on the field populations of the two species of GAS in various districts. We explore the differences in the invasive characteristics of the two species of snails in terms of their dietary intake, cold adaptation and drought resistance. The results indicate that, based on the phylogenetic tree analysis, more than half of the sampled snails exhibit higher similarity to A. immaculata. The number of wild A. immaculata is significantly greater than that of A. fulica, and 70.64% of the 746 GAS are A. immaculata. At the same time, it is also found that the maximum shell length of A. immaculata is 135.83 mm, with an average shell length of 76.00 mm, which is significantly different from the average shell length of A. fulica (56.57 mm, p < 0.01). The food intake assay shows that there is no difference in the food preferences of the two species, but the food demand of A. immaculata is significantly greater than that of A. fulica (2.32 fold, p < 0.01). In the cold adaptation assay, A. immaculata recovers from the cold dormancy state significantly faster than A. fulica (1.92 fold, p < 0.05), and the speed with which A. immaculata enters the dormancy state in the drought environment is significantly slower than that of A. fulica (0.706 fold, p < 0.05). With the characteristics of a large body size, large food intake and strong resistance to cold and drought resistance, A. immaculata has the potential to be dominant in competition with A. fulica in the same ecological niche, and it has become the main invasive species of GAS in Shenzhen. [ABSTRACT FROM AUTHOR]

Simple Summary: Turano-Mongolian cattle breeds are known for adaptation to extreme environmental conditions and for outstanding production traits. The Buryat and Wagyu Turano-Mongolian breeds are characterised by adaptation to harsh climates and poor forage, and top-quality marbled meat, respectively. In our study, we explored the genomes of these breeds to learn about the selection underlying these traits. A set of scans for genetic signatures of selection using complementary approaches allowed us to reveal candidate genes and variants likely shaping the biology of Buryat and Wagyu breeds. These findings could help with livestock improvement efforts. Past and ongoing selection shapes the genomes of livestock breeds. Identifying such signatures of selection allows for uncovering the genetic bases of affected phenotypes, including economically important traits and environmental adaptations, for the further improvement of breed genetics to respond to climate and economic challenges. Turano-Mongolian cattle are a group of taurine breeds known for their adaptation to extreme environmental conditions and outstanding production performance. Buryat Turano-Mongolian cattle are among the few breeds adapted to cold climates and poor forage. Wagyu, on the other hand, is famous for high productivity and unique top-quality marbled meat. We used hapFLK, the de-correlated composite of multiple signals (DCMS), PBS, and FST methods to search for signatures of selection in their genomes. The scans revealed signals in genes related to cold adaptation (e.g., STAT3, DOCK5, GSTM3, and CXCL8) and food digestibility (SI) in the Buryat breed, and growth and development traits (e.g., RBFOX2 and SHOX2) and marbling (e.g., DGAT1, IQGAP2, RSRC1, and DIP2B) in Wagyu. Several putatively selected genes associated with reproduction, immunity, and resistance to pathogens were found in both breed genomes. The results of our work could be used for creating new productive adapted breeds or improving the extant breeds. [ABSTRACT FROM AUTHOR]

Adenosine kinase (ADK) is a key enzyme widely distributed in plants, playing an important role in maintaining cellular energy homeostasis and regulating plant growth, development, and responses to environmental stresses. However, research on ADK genes in cotton (Gossypium hirsutum), an economically significant crop, has been limited. This study identified 92 ADK genes from four cotton species (G. arboreum, G. raimondii, G. hirsutum, and G. barbadense) using HMMER and Local BLASTP methods and classified them into six groups. Chromosomal localization revealed a random distribution of ADK genes in G. hirsutum, with 13 genes located on the At subgenome and 14 genes on the Dt subgenome. Gene structure analysis showed consistency in exon–intron organization within subgroups, while conserved motif analysis identified subgroup-specific motifs, indicating functional diversity. Synteny and collinearity mapping analysis revealed that the primary expansion mechanisms of the ADK gene family in cotton are polyploidy and segmental duplication. Cis-regulatory elements in GhADK promoters were classified into light response, hormone response, developmental regulation, and stress response. We also analyzed the expression patterns of GhADK genes under a low temperature (4 °C) and drought conditions. Most GhADK genes responded to cold stress with different expression patterns, indicating their roles in rapid response and long-term cold adaptation. Under drought stress, expression patterns varied, with some genes showing sustained high expression levels. The qRT-PCR validation of transcriptomic data confirmed the stress-induced expression patterns of selected GhADK genes. Functional analysis through the VIGS silencing of GhADK25 demonstrated its importance in cold and drought stress responses, with silencing resulting in poor growth under stress, highlighting its significance in stress tolerance. This study provides a basis for further understanding the evolutionary relationships and functions of the cotton ADK gene family. [ABSTRACT FROM AUTHOR]

The Enshi black pig is a Chinese native breed known for its rich nutrition content and high quality, which has notable traction in the consumer market. In this study, the potential impact of the main commercial cuts from Enshi black pork carcasses (ham, loin, and belly) on the bacteria community of spoiled meat under refrigerated storage (4 °C) was assessed by using a high-throughput sequencing method. Moreover, the spoilage potential of isolated strains from spoiled pork was investigated. The results demonstrated significant differences (p < 0.05) in bacterial community diversity and composition among spoiled ham, loin, and belly samples. Linear discriminant analysis effect size (LEfSe) analysis revealed a total of 20 significantly different potential bacterial biomarkers, with the dominant genera of Pseudomonas, Psychrobacter, Shewanella and Carnobacterium. Additionally, C. divergens THT1-5, isolated from spoiled ham samples, displayed cold adaptation and higher spoilage potential in Enshi black pork. These findings are helpful for identifying key factors contributing to spoilage in Enshi black pork and developing strategies to inhibit bacterial growth during preservation. [ABSTRACT FROM AUTHOR]

Increasing the number of resistant bacteria resistant to treatment is one of the leading causes of death worldwide. These bacteria are created in wounds and injuries and can be transferred through hospital equipment. Various attempts have been made to treat these bacteria in recent years, such as using different drugs and new sterilization methods. However, some bacteria resist drugs, and other traditional methods cannot destroy them. In the meantime, various studies have shown that cold atmospheric plasma can kill these bacteria through different mechanisms, making cold plasma a promising tool to deactivate bacteria. This new technology can be effectively used in the food industry because it has the potential to inactivate microorganisms such as spores and microbial toxins and increase the wettability and printability of polymers to pack fresh and dried food. It can also increase the shelf life of food without leaving any residue or chemical effluent. This paper investigates cold plasma's potential, advantages, and disadvantages in the food industry and sterilization. [ABSTRACT FROM AUTHOR]

The permafrost in Northeast China is experiencing rapid degradation due to the influence of climate change and human activities, profoundly impacting the local ecological environment and engineering construction. Understanding the spatiotemporal dynamics of long-term permafrost in this region is crucial; however, systematic research on this topic remains scarce. This study combines meteorological station data, MODIS land surface temperature (LST) datasets, and borehole locations to apply the surface frost number (SFn) model. This approach enables the simulation and estimation of the spatial distribution and changes in the area of the surface frost number without vegetation effects (SFnv) and permafrost temperature (PT) in Northeast China from 1971 to 2020. The area of the SFnv > 0.49 within the permafrost region decreased substantially from approximately 44.353 × 104 km2 to 19.909 × 104 km2 between 1971 and 2020, with a notable change in 1988. The area of permafrost calculated using PT < 0 was slightly smaller, declining from 39.388 × 104 km2 to 29.852 × 104 km2. There was also a significant increase in the area with PT ranging from −1 °C to 0 °C, indicating a decline in permafrost stability. Approximately 10.926 × 104 km2 of stable permafrost has been transformed into semi-stable and unstable permafrost. Moreover, from 1982 to 2020, the NDVI was negatively correlated with the area of stable permafrost and positively correlated with the area of transitional or unstable permafrost. Vegetation cover decreased as transitional or unstable permafrost degraded. These findings provide valuable information for permafrost research and engineering development in cold regions, as well as for future planning and adaptation strategies. [ABSTRACT FROM AUTHOR]

Extreme weather poses huge challenges for animals that must adapt to wide variations in environmental temperature and, in many cases, it can lead to the local extirpation of populations or even the extinction of an entire species. Previous studies have found that one element of amphibian adaptation to environmental stress involves changes in mitochondrial gene expression at low temperatures. However, to date, comparative studies of gene expression in organisms living at extreme temperatures have focused mainly on nuclear genes. This study sequenced the complete mitochondrial genomes of five Asian hylid frog species: Dryophytes japonicus, D. immaculata, Hyla annectans, H. chinensis and H. zhaopingensis. It compared the phylogenetic relationships within the Hylidae family and explored the association between mitochondrial gene expression and evolutionary adaptations to cold stress. The present results showed that in D. immaculata, transcript levels of 12 out of 13 mitochondria genes were significantly reduced under cold exposure (p < 0.05); hence, we put forward the conjecture that D. immaculata adapts by entering a hibernation state at low temperature. In H. annectans, the transcripts of 10 genes (ND1, ND2, ND3, ND4, ND4L, ND5, ND6, COX1, COX2 and ATP8) were significantly reduced in response to cold exposure, and five mitochondrial genes in H. chinensis (ND1, ND2, ND3, ND4L and ATP6) also showed significantly reduced expression and transcript levels under cold conditions. By contrast, transcript levels of ND2 and ATP6 in H. zhaopingensis were significantly increased at low temperatures, possibly related to the narrow distribution of this species primarily at low latitudes. Indeed, H. zhaopingensis has little ability to adapt to low temperature (4 °C), or maybe to enter into hibernation, and it shows metabolic disorder in the cold. The present study demonstrates that the regulatory trend of mitochondrial gene expression in amphibians is correlated with their ability to adapt to variable climates in extreme environments. These results can predict which species are more likely to undergo extirpation or extinction with climate change and, thereby, provide new ideas for the study of species extinction in highly variable winter climates. [ABSTRACT FROM AUTHOR]

The study of cold-tolerance mechanisms of wheat as a leading cereal crop is very relevant to science. Primary metabolites play an important role in the formation of increased cold tolerance. The aim of this research is to define changes in the content of primary metabolites (soluble proteins and sugars), growth, and photosynthetic apparatus of freezing-tolerant and cold-sustainable wheat (Triticum aestivum L.) genotypes under optimal conditions and after prolonged (7 days) exposure to low temperature (4 °C). In order to gain a deeper comprehension of the mechanisms behind wheat genotypes' adaptation to cold, we determined the expression levels of photosynthetic genes (RbcS, RbcL) and genes encoding cold-regulated proteins (Wcor726, CBF14). The results indicated different cold-adaptation strategies of freezing-tolerant and cold-sustainable wheat genotypes, with soluble proteins and sugars playing a significant role in this process. In plants of freezing-tolerant genotypes, the strategy of adaptation to low temperature was aimed at increasing the content of soluble proteins and modification of carbohydrate metabolism. The accumulation of sugars was not observed in wheat of cold-sustainable genotypes during chilling, but a high content of soluble proteins was maintained both under optimal conditions and after cold exposure. The adaptation strategies of wheat genotypes differing in cold tolerance were related to the expression of photosynthetic genes and genes encoding cold-regulated proteins. The data improve our knowledge of physiological and biochemical mechanisms of wheat cold adaptation. [ABSTRACT FROM AUTHOR]

There have been fruitful publications on thermal comfort of urban residential buildings in China. However, there is a lack of reviews on this topic to perform a comprehensive analysis and find opportunities to meet occupants' thermal comfort needs while improving building energy efficiencies. This paper addresses this issue by presenting a systematic review on the advancements in research on thermal comfort in urban residential buildings in China. Firstly, two common thermal comfort research approaches, i.e., field studies and laboratory studies, are discussed. Secondly, eleven main thermal comfort evaluation indicators are summarized. Finally, this paper analyzes the thermal comfort survey data from different researchers, discusses the impacts of adaptive behaviors on human thermal comfort, and provides recommendations for future research on urban residential thermal comfort. It was found that people have higher and higher requirements for their indoor thermal environment as time goes by, especially in the winter; the thermoneutral temperature is higher in warmer climate regions in the summer but lower in the winter than in colder climate regions; the thermoneutral temperature tends to increase with the indoor air temperature due to an adaptation to the indoor thermal environment. The outcomes of this paper provide valuable information on thermal comfort behaviors of urban residents in different climate zones in China, which can serve as a resource for the academic community conducting future research on thermal comfort and assist policymakers in enhancing building energy efficiencies without compromising the occupants' comfort. [ABSTRACT FROM AUTHOR]

Global climate change, which is connected to global warming and changes in weather patterns, affects various parts of the environment, including the growth/development of plants. Generally, a number of plant species are capable of acquiring tolerance to frost after exposure to cold (in the cold-acclimation/cold-hardening process). In the last few decades, there have been more and more frequent periods of higher temperatures—warm periods that, e.g., break down the process of cold acclimation. This generates deacclimation, which could stimulate growth and lower frost tolerance in plants. Generally, deacclimation causes the reversal of changes induced by cold acclimation (i.e., in concentration of sugars, accumulation of protective proteins, or hormonal homeostasis). Unlike cold acclimation, the phenomenon of deacclimation has been less studied. The aim of this article was (1) to briefly describe the problem of deacclimation, with more attention being paid to its significance for economically important winter crop species, (2) to review and characterize the physiological-biochemical changes that are induced in plants by deacclimation, and (3) to discuss the possibilities of detecting deacclimation earlier in order to counteract its effects on crops. [ABSTRACT FROM AUTHOR]

Peaches and nectarines have a short shelf life even when harvested at appropriate physiological maturity. Market life is increased by storage at low temperatures. However, chilling injury symptoms can appear, causing physiological disorders and limiting shipping potential. The rootstock effect on the post-harvest quality has hardly been explored. Thus, the principal aim of this work was to study the influence of seven different Prunus rootstocks on the "Big Top" nectarine cv, considering harvest and post-harvest quality parameters and their correlation with chilling injury disorders. Basic fruit quality traits, individual sugars and organic acids analyzed by HPLC and other biochemical compounds such as relative antioxidant capacity, total phenolics content, flavonoids, anthocyanins, vitamin C and related enzyme activities (PAL, POD, PPO) were considered. In addition, correlations with possible candidate genes for chilling injury (CI) tolerance were searched by qPCR. Although a low susceptibility to CI symptoms has been found in "Big Top", rootstocks "PADAC 9902-01", "PADAC 99-05" and "ReplantPAC" exhibited lower CI symptoms. A statistically significant influence of the evaluated rootstocks was found concerning the parameters of this study. Phenols and anthocyanins seem to be important parameters to be considered in the prevention of chilling injury disorders. Moreover, PAL1, PPO4, PG2 and LDOX genes relative expressions were positively associated with chilling injury susceptibility. This study opens new perspectives for understanding peach fruit adaptation and response to cold storage temperatures during the post-harvest period. [ABSTRACT FROM AUTHOR]

Alfalfa (Medicago sativa) is a perennial forage legume that is widely distributed all over the world; therefore, it has an extremely complex genetic background. Though population structure and phylogenetic studies have been conducted on a large group of alfalfa nuclear genomes, information about the chloroplast genomes is still lacking. Chloroplast genomes are generally considered to be conservative and play an important role in population diversity analysis and species adaptation in plants. Here, 231 complete alfalfa chloroplast genomes were successfully assembled from 359 alfalfa resequencing data, on the basis of which the alfalfa chloroplast pan-genome was constructed. We investigated the genetic variations of the alfalfa chloroplast genome through comparative genomic, genetic diversity, phylogenetic, population genetic structure, and haplotype analysis. Meanwhile, the expression of alfalfa chloroplast genes under cold stress was explored through transcriptome analysis. As a result, chloroplast genomes of 231 alfalfa lack an IR region, and the size of the chloroplast genome ranges from 125,192 bp to 126,105 bp. Using population structure, haplotypes, and construction of a phylogenetic tree, it was found that alfalfa populations could be divided into four groups, and multiple highly variable regions were found in the alfalfa chloroplast genome. Transcriptome analysis showed that tRNA genes were significantly up-regulated in the cold-sensitive varieties, while rps7, rpl32, and ndhB were down-regulated, and the editing efficiency of ycf1, ycf2, and ndhF was decreased in the cold-tolerant varieties, which may be due to the fact that chloroplasts store nutrients through photosynthesis to resist cold. The huge number of genetic variants in this study provide powerful resources for molecular markers. [ABSTRACT FROM AUTHOR]

Simple Summary: The effects of Quaternary climatic oscillations on lineage diversification and demography of organisms in drylands have drawn much attention recently. However, little is still known about the processes that shaped the species' spatial genetic structure in areas such as the arid Central Asia, particularly for animals in Northwest China. Here, we investigated the genetic structure and population dynamics of the Zaisan toad-headed agama (Phrynocephalus melanurus) by combining mtDNA phylogeography and species distribution models (SDMs) with range-wide sampling for the first time. Phylogenetic analyses recovered two main Clades, with one from Dzungar and Alakol basins being geographically sub-structured into several groups. Lineage diversification took place in the Pleistocene, coinciding with the drastic aridification caused by Quaternary climatic transitions and drastic activity of the Tianshan Mountains. Moreover, populations of the Dzungar Basin experienced the past expansion and parapatric divergence contributed by isolation-by-distance. SDMs unveiled the species range dynamics since the late Pleistocene, showing expansion in interglacial, and contraction during last glacial maximum and late Holocene periods. Future distribution projections demonstrated drastic habitat loss, suggesting the significance of conservation effort. Our findings highlight the significance of combining genetic approaches with environmental data when evaluating the effects of Pleistocene climatic oscillations. The agamid lizard Phrynocephalus melanurus is restricted to Northwest China (Dzungar Basin) and the adjacent Eastern Kazakhstan (Zaisan and Alakol basins). To elucidate the phylogeography of P. melanurus, we obtained the mitochondrial DNA COI segments of 175 sampled lizards from 44 localities across the whole distribution. Phylogenetic analyses revealed two main Clades comprising five geographically structured lineages (I, IIa, IIb1, IIb2, and IIb3) that fit an isolation-by-distance (IBD) model. The divergence from the most recent common ancestor was dated to ~1.87 million years ago (Ma). Demographic analyses demonstrated lineage-specific response to past climate change: stable population for Clade I, Subclade IIb1; past population expansion for IIb3 since 0.18 Ma, respectively. Bayesian phylogeographic diffusion analyses detected initial spreading at the Saur Mount vicinity, approximately 1.8 Ma. Historical species distribution model (SDM) projected expansion of the suitable habitat in the last interglacial and shift and contraction in the last glacial maximum and Holocene epochs. The SDM predicted a drastic reduction in suitable area throughout the range as a response to future climate change. Our findings suggest that the evolution of P. melanurus followed a parapatric divergence with subsequent dispersal and adaptation to cold and dry environments during the Quaternary. Overall, this work improves our understanding of the lineage diversification and population dynamics of P. melanurus, providing further insights into the evolutionary processes that occurred in Northwest China and adjacent Eastern Kazakhstan. [ABSTRACT FROM AUTHOR]

The negative impacts of climate change on native forest ecosystems have created challenging conditions for the sustainability of natural forest regeneration. These challenges arise primarily from abiotic stresses that affect the early stages of forest tree development. While there is extensive evidence on the diversity of juvenile microbial symbioses in agricultural and fruit crops, there is a notable lack of reports on native forest plants. This review aims to summarize the critical studies conducted on the diversity of juvenile plant–microbe interactions in forest plants and to highlight the main benefits of beneficial microorganisms in overcoming environmental stresses such as drought, high and low temperatures, metal(loid) toxicity, nutrient deficiency, and salinity. The reviewed studies have consistently demonstrated the positive effects of juvenile plant–microbiota interactions and have highlighted the potential beneficial attributes to improve plantlet development. In addition, this review discusses the beneficial attributes of managing juvenile plant–microbiota symbiosis in the context of native forest restoration, including its impact on plant responses to phytopathogens, promotion of nutrient uptake, facilitation of seedling adaptation, resource exchange through shared hyphal networks, stimulation of native soil microbial communities, and modulation of gene and protein expression to enhance adaptation to adverse environmental conditions. [ABSTRACT FROM AUTHOR]

Simple Summary: Dung beetle communities include three groups of insects: the true dung beetles (scarabaeines), the small dung beetles (aphodiines), and the earth-boring dung beetles (geotrupids). The Italian dung beetle fauna is one of the richest in Europe due to the position of the Italian peninsula in the middle of the Mediterranean global hotspot of biodiversity. Dung beetle faunas in the Italian peninsula appear to be richer than that of Sardinia, which has a distinctly impoverished fauna due to its strong isolation from the mainland. Dung beetle species richness varies along the Italian peninsula in response to climatic factors. Aphodiines (that need to use the dung before it dries) are mainly associated with humid and cold climates and do not show a latitudinal pattern, while scarabaeines (which can cope with dry conditions) increase their diversity southward. Dung beetle species composition in Italian regions reflects both random processes of dispersal (possibly favored by human influences due to millennia of grazing activities) and the role of southern areas as refugia during Pleistocene glacials. The Italian fauna includes about 170 species/subspecies of dung beetles, being one of the richest in Europe. We used data on dung beetle distribution in the Italian regions to investigate some macroecological patterns. Specifically, we tested if species richness decreased southward (peninsula effect) or northward (latitudinal gradient). We also considered the effects of area (i.e., the species–area relationship), topographic complexity, and climate in explaining dung beetle richness. Finally, we used multivariate techniques to identify biotic relationships between regions. We found no support for the peninsula effect, whereas scarabaeines followed a latitudinal gradient, thus supporting a possible role of southern areas as Pleistocene refuges for this group of mainly thermophilic beetles. By contrast, aphodiines were more associated with cold and humid climates and do not show a distinct latitudinal pattern. In general, species richness was influenced by area, with the Sardinian fauna being however strongly impoverished because of its isolation. Faunal patterns for mainland regions reflect the influence of current ecological settings and historical factors (Pleistocene glaciations) in determining species distributions. [ABSTRACT FROM AUTHOR]

In this study, Mesorhizobium sp. PAMC28654 was isolated from a soil sample collected from the polar region of Uganda. Whole-genome sequencing and comparative genomics were performed to better understand the genomic features necessary for Mesorhizobium sp. PAMC28654 to survive and thrive in extreme conditions and stresses. Additionally, diverse sequence analysis tools were employed for genomic investigation. The results of the analysis were then validated using wet-lab experiments. Genome analysis showed trace elements' resistant proteins (CopC, CopD, CzcD, and Acr3), exopolysaccharide (EPS)-producing proteins (ExoF and ExoQ), and nitrogen metabolic proteins (NarG, NarH, and NarI). The strain was positive for nitrate reduction. It was tolerant to 100 mM NaCl at 15 °C and 25 °C temperatures and resistant to multiple trace elements (up to 1 mM CuSO4·5H2O, 2 mM CoCl2·6H2O, 1 mM ZnSO4·7H2O, 0.05 mM Cd(NO3)2·4H2O, and 100 mM Na2HAsO4·7H2O at 15 °C and 0.25 mM CuSO4·5H2O, 2 mM CoCl2·6H2O, 0.5 mM ZnSO4·7H2O, 0.01 mM Cd(NO3)2·4H2O, and 100 mM Na2HAsO4·7H2O at 25 °C). This research contributes to our understanding of bacteria's ability to survive abiotic stresses. The isolated strain can be a potential candidate for implementation for environmental and agricultural purposes. [ABSTRACT FROM AUTHOR]

The paper mulberry is a commonly found tree species with a long history of cultivation. It also serves as a crucial case study for understanding how woody plants adapt to low temperatures. Under cold treatment, we observed a substantial number of alternative splicing (AS) genes, showcasing the intricate landscape of AS events. We have detected all seven types of AS events, with the alternative 3′ splice site (A3) having the most. We observed that many genes that underwent differential AS were significantly enriched in starch and sucrose metabolism and circadian rhythm pathways. Moreover, a considerable proportion of differentially spliced genes (DSGs) also showed differential expression, with 20.38% and 25.65% under 12 h and 24 h cold treatments, respectively. This suggests a coordinated regulation between gene AS and expression, playing a pivotal role in the paper mulberry's adaptation to cold stress. We further investigated the regulatory mechanisms of AS, identifying 41 serine/arginine-rich (SR) splicing factors, among which 11 showed differential expression under cold treatment, while 29 underwent alternative splicing. Additionally, genes undergoing AS displayed significantly higher DNA methylation levels under cold stress, while normal splicing (non-AS) genes exhibited relatively lower methylation levels. These findings suggest that methylation may play an important role in governing gene AS. Finally, our research will provide useful information on the role of AS in the cold acclimation tolerance of the paper mulberry. [ABSTRACT FROM AUTHOR]

Simple Summary: In the present study, we investigated the effects of two intermittent cold stimulation conditions (3 °C and 9 °C below the normal brooding temperature) on the neuroendocrine and cardiac substance metabolism pathways in broilers. We analyzed the transcriptome and the expression levels of neuroendocrine substances in serum, the mRNA expression of cardiac substance metabolism-related genes and heat-shock proteins. The results of our study showed that mild cold stimulation (at 3 °C lower than the normal temperature) can activate the neuroendocrine pathway release neurotransmitters and improve cardiac substance metabolism to protect the broilers from cold stress damage. This study aimed to investigate the impact of cold adaptation on the neuroendocrine and cardiac substance metabolism pathways in broilers. The broilers were divided into the control group (CC), cold adaptation group (C3), and cold-stressed group (C9), and experimental period was divided into the training period (d 1–35), recovery period (d 36–43), and cold stress period (d 43–44). During the training period, the CC group was reared at ambient temperature, while C3 and C9 groups were reared at 3 °C and 9 °C lower than the ambient temperature, respectively, for 5 h/d at 1 d intervals. During the recovery period, all the groups were maintained at 20 °C. Lastly, during the cold stress period, the groups were divided into two sub-groups, and each sub-group was placed at 10 °C for 12 h (Y12) or 24 h (Y24) for acute cold stimulation. The blood, hypothalamic, and cardiac tissues samples were obtained from all the groups during the training, recovery, and acute stress periods. The results revealed that the transcription of calcium voltage-gated channel subunit alpha 1 C (CACNAIC) was increased in the hypothalamic tissues of the C3 group (p < 0.05). Moreover, compared to the CC group, the serum norepinephrine (NE) was increased in the C9 group (p < 0.05), but insulin (INS) was decreased in the C9 group (p < 0.05). In addition, the transcription of the phosphoinositide-3 kinase (PI3K), protein kinase B (Akt), mammalian target of rapamycin (mTOR), SREBP1c, FASN, ACC1, and SCD genes was down-regulated in the C3 and C9 groups (p < 0.05); however, their expression increased in the C3 and C9 groups after acute cold stimulation (p < 0.05). Compared to the CC group, the transcription of forkhead box O1 (FoxO1), PEPCK, G6Pase, GLUT1, HK1, PFK, and LDHB genes was up-regulated in the C3 and C9 groups (p < 0.05. Furthermore, compared to the CC and C9 groups, the protein and mRNA expressions of heat shock protein (HSP) 70 and HSP90 were significantly increased in the C3 group (p < 0.05). These results indicate that intermittent cold training can enhance cold stress tolerance in broilers by regulating their neuroendocrine and cardiac substance metabolism pathways. [ABSTRACT FROM AUTHOR]

Ectothermic fish exposure to hypothermal stress requires adjusting their metabolic molecular machinery, which was investigated using Indian medaka (Oryzias dancena; 10 weeks old, 2.5 ± 0.5 cm) cultured in fresh water (FW) and seawater (SW; 35‰) at room temperature (28 ± 1 °C). The fish were fed twice a day, once in the morning and once in the evening, and the photoperiod was 12 h:12 h light: dark. In this study, we applied two hypothermal treatments to reveal the mechanisms of energy metabolism via pgc-1α regulation in the gills of Indian medaka; cold-stress (18 °C) and cold-tolerance (extreme cold; 15 °C). The branchial ATP content was significantly higher in the cold-stress group, but not in the cold-tolerance group. In FW- and SW-acclimated medaka, the expression of genes related to mitochondrial energy metabolism, including pgc-1α, prc, Nrf2, tfam, and nd5, was analyzed to illustrate differential responses of mitochondrial energy metabolism to cold-stress and cold-tolerance environments. When exposed to cold-stress, the relative mRNA expression of pgc-1α, prc, and Nrf2 increased from 2 h, whereas that of tfam and nd5 increased significantly from 168 h. When exposed to a cold-tolerant environment, prc was significantly upregulated at 2 h post-cooling in the FW and SW groups, and pgc-1α was significantly upregulated at 2 and 12 h post-cooling in the FW group, while tfam and nd5 were downregulated in both FW and SW fish. Hierarchical clustering revealed gene interactions in the cold-stress group, which promoted diverse mitochondrial energy adaptations, causing an increase in ATP production. However, the cold-tolerant group demonstrated limitations in enhancing ATP levels through mitochondrial regulation via the PGC-1α energy metabolism pathway. These findings suggest that ectothermic fish may develop varying degrees of thermal tolerance over time in response to climate change. This study provides insights into the complex ways in which fish adjust their metabolism when exposed to cold stress, contributing to our knowledge of how they adapt. [ABSTRACT FROM AUTHOR]

Pigs are susceptible to cold stress due to the absence of brown fat caused by the partial deletion of uncoupling protein 1 during their evolution. Some local pig breeds in China exhibit potential cold adaptability, but research has primarily focused on fat and intestinal tissues. Skeletal muscle plays a key role in adaptive thermogenesis in mammals, yet the molecular mechanism of cold adaptation in porcine skeletal muscle remains poorly understood. This study investigated the cold adaptability of two pig breeds, Mashen pigs (MS) and Large White pigs (LW), in a four-day cold (4 °C) or normal temperature (25 °C) environment. We recorded phenotypic changes and collected blood and longissimus dorsi muscle for transcriptome sequencing. Finally, the PRSS8 gene was randomly selected for functional exploration in porcine skeletal muscle satellite cells. A decrease in body temperature and body weight in both LW and MS pigs under cold stress, accompanied by increased shivering frequency and respiratory frequency, were observed. However, the MS pigs demonstrated stable physiological homeostasis, indicating a certain level of cold adaptability. The LW pigs primarily responded to cold stress by regulating their heat production and glycolipid energy metabolism. The MS pigs exhibited a distinct response to cold stress, involving the regulation of heat production, energy metabolism pathways, and robust mitochondrial activity, as well as a stronger immune response. Furthermore, the functional exploration of PRSS8 in porcine skeletal muscle satellite cells revealed that it affected cellular energy metabolism and thermogenesis by regulating ERK phosphorylation. These findings shed light on the diverse transcriptional responses of skeletal muscle in LW and MS pigs under cold stress, offering valuable insights into the molecular mechanisms underlying cold adaptation in pigs. [ABSTRACT FROM AUTHOR]

Patterns of species diversity have been associated with changes in climate across latitude and elevation. However, the ecological and evolutionary mechanisms underlying these relationships are still actively debated. Here, we present a complementary view of the well-known tropical niche conservatism (TNC) hypothesis, termed the multiple zones of origin (MZO) hypothesis, to explore mechanisms underlying latitudinal and elevational gradients of phylogenetic diversity in tree communities. The TNC hypothesis posits that most lineages originate in warmer, wetter, and less seasonal environments in the tropics and rarely colonize colder, drier, and more seasonal environments outside of the tropical lowlands, leading to higher phylogenetic diversity at lower latitudes and elevations. In contrast, the MZO hypothesis posits that lineages also originate in temperate environments and readily colonize similar environments in the tropical highlands, leading to lower phylogenetic diversity at lower latitudes and elevations. We tested these phylogenetic predictions using a combination of computer simulations and empirical analyses of tree communities in 245 forest plots located in six countries across the tropical and subtropical Andes. We estimated the phylogenetic diversity for each plot and regressed it against elevation and latitude. Our simulated and empirical results provide strong support for the MZO hypothesis. Phylogenetic diversity among co-occurring tree species increased with both latitude and elevation, suggesting an important influence on the historical dispersal of lineages with temperate origins into the tropical highlands. The mixing of different floras was likely favored by the formation of climatically suitable corridors for plant migration due to the Andean uplift. Accounting for the evolutionary history of plant communities helps to advance our knowledge of the drivers of tree community assembly along complex climatic gradients, and thus their likely responses to modern anthropogenic climate change. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of recycling agent composition on the recycling effect of aged asphalt in the cold recycling process, the design and optimization of cold recycling agent composition were performed through the central composite design-response surface method combined with the dynamic shear rheometer (DSR) test and the bending beam rheometer (BBR) test. The molecular weight distribution and component changes in aged asphalt before and after the addition of a cold recycling agent were also analyzed by gel permeation chromatography (GPC) and hydrogen-flame ionization test. The results showed that the permeable cold recycling agent has a recycling effect on the aged asphalt, but its effectiveness is greatly affected by recycling agent composition. The best recycling effect was achieved when the ratio of aromatic oil and penetrant in the cold recycling agent was 61.2:38.8, respectively. In terms of the recycling agent and aromatic functional groups in the aromatic oil, the aromatics in the recycling agent are derived from the aromatic oils, and the penetrant is only fused and permeated with the aromatic oils. After the admixture of the cold recycling agent, the penetrant in the recycling agent allows the aromatic oil to enter the aged asphalt at room temperature. The light components volatilized by aging are replenished, allowing the aged asphalt to recover some of its properties. [ABSTRACT FROM AUTHOR]

Tibetan sheep are already well adapted to cold season nutrient stress on the Tibetan Plateau. Rumen, an important nutrient for metabolism and as an absorption organ in ruminants, plays a vital role in the cold stress adaptations of Tibetan sheep. Ruminal microbiota also plays an indispensable role in rumen function. In this study, combined multiomics data were utilized to comprehensively analyze the interaction mechanism between rumen epithelial miRNAs and microbiota and their metabolites in Tibetan sheep under nutrient stress in the cold season. A total of 949 miRNAs were identified in the rumen epithelium of both cold and warm seasons. A total of 62 differentially expressed (DE) miRNAs were screened using FC > 1.5 and p value < 0.01, and a total of 20,206 targeted genes were predicted by DE miRNAs. KEGG enrichment analysis revealed that DE miRNA-targeted genes were mainly enriched in axon guidance(ko04360), tight junction(ko04530), inflammatory mediator regulation of TRP channels(ko04750) and metabolism-related pathways. Correlation analysis revealed that rumen microbiota, rumen VFAs and DE miRNAs were all correlated. Further study revealed that the targeted genes of cold and warm season rumen epithelial DE miRNAs were coenriched with differential metabolites of microbiota in glycerophospholipid metabolism (ko00564), apoptosis (ko04210), inflammatory mediator regulation of TRP channels (ko04750), small cell lung cancer (ko05222), and choline metabolism in cancer (ko05231) pathways. There are several interactions between Tibetan sheep rumen epithelial miRNAs, rumen microbiota, and microbial metabolites, mainly through maintaining rumen epithelial barrier function and host homeostasis of choline and cholesterol, improving host immunity, and promoting energy metabolism pathways, thus enabling Tibetan sheep to effectively respond to cold season nutrient stress. The results also suggest that rumen microbiota have coevolved with their hosts to improve the adaptive capacity of Tibetan sheep to cold season nutrient stress, providing a new perspective for the study of cold season nutritional stress adaptation in Tibetan sheep. [ABSTRACT FROM AUTHOR]

Ammopiptanthus mongolicus, a traditional ethnic medicinal herb, is a rare broad-leaved evergreen shrub in the arid region of central Asia that can survive under extremely low temperatures during winter. In this study, we investigated the cold stress response of A. mongolicus leaves using physiological and proteomic approaches. Cold stress treatment increased the relative electrolyte leakage, proline, and soluble sugar levels and decreased the chlorophyll content in A. mongolicus leaves. Moreover, 93 differentially abundant proteins (DAPs) were identified using two-dimensional electrophoresis, of which 79 were further confirmed via tandem mass spectrometric analysis. The predicted functions of DAPs were mainly associated with photosynthesis in chloroplasts, reactive oxygen species scavenging, defense, and protein synthesis, folding, and degradation. A. mongolicus chitinase A (AmCHIA) is a cold-induced apoplast protein whose transcription is upregulated under cold, osmotic, high-salinity, and mechanical stresses. Recombinant AmCHIA expressed in Escherichia coli exhibits chitinase activity. Here, AmCHIA expression enhanced the cold tolerance of E. coli cells, suggesting that it may contribute to the cold adaptation of A. mongolicus after cold treatment. The present study not only provides important data for understanding the cold stress responses in plants but also serves as a basis for further exploration of the biological functions of cold-induced proteins in A. mongolicus using genetic approaches. [ABSTRACT FROM AUTHOR]

Based on the serious phenomenon of Tibetan sheep "growing strong in warm seasons and losing weight in cold seasons", this study explores the regulation of lncRNAs, microbiota, and metabolites in the cold season adaptation of Tibetan sheep from the perspective of the co-evolution of the host genome (first genome) and microbiome (second genome). RNA-seq results showed that 172 DE lncRNAs were identified in the rumen epithelium of Tibetan sheep in warm and cold seasons, of which 87 DE lncRNAs were significantly up-regulated in cold seasons. KEGG enrichment showed that target genes of up-regulated lncRNAs were significantly enriched in TNF signaling and oxidative phosphorylation pathways. LncRNA-mRNA regulatory network indicated that DE lncRNAs were involved in nutrient stress in the cold season by targeting ATP1B2, CADPS, TLR5, and UGT1A6. Correlation analysis showed some lncRNAs were significantly correlated with acetic acid, propionic acid, butyric acid, and rumen epithelial histomorphology and had a negative correlation with Butyrivibrio-2 and Succiniclasticum (p < 0.05). In addition, differential metabolites bilirubin and lncRNAs were co-enriched in the bile secretion pathway. lncRNAs played an important role in the adaptation process of Tibetan sheep in the cold season, and mediate the host to participate in nutrient absorption, energy utilization, and immune response, indicating that the host genome and microbial genome promote Tibetan sheep to adapt to nutrient stress in the cold season through co-evolution. [ABSTRACT FROM AUTHOR]

High-mountain and arctic plants are considered especially sensitive to climate change because of their close adaptation to the cold environment. Kalmia procumbens, a typical arctic–alpine species, reaches southernmost European localities in the Pyrenees and Carpathians. The aim of this study was the assessment and comparison of the current potential niche areas of K. procumbens in the Pyrenees and Carpathians and their possible reduction due to climate change, depending on the scenario. The realized niches of K. procumbens in the Pyrenees are compact, while those in the Carpathians are dispersed. In both mountain chains, the species occurs in the alpine and subalpine vegetation belts, going down to elevations of about 1500–1600 m, while the most elevated localities in the Pyrenees are at ca. 3000 m, about 500 m higher than those in the Carpathians. The localities of K. procumbens in the Carpathians have a more continental climate than those in the Pyrenees, with lower precipitation and temperatures but higher seasonality of temperature and precipitation. The species covered a larger area of geographic range during the Last Glacial Maximum, but its geographic range was reduced during the mid-Holocene. Due to climate warming, a reduction in the potential area of occurrence could be expected in 2100; this reduction is expected to be strong in the Carpathians and moderate in the Pyrenees. [ABSTRACT FROM AUTHOR]

Alginate oligosaccharides (AOs) prepared through enzymatic reaction by diverse alginate lyases under relatively controllable and moderate conditions possess versatile biological activities. But widely used commercial alginate lyases are still rather rare due to their poor properties (e.g., lower activity, worse thermostability, ion tolerance, etc.). In this work, the alginate lyase Alyw208, derived from Vibrio sp. W2, was expressed in Yarrowia lipolytica of food grade and characterized in order to obtain an enzyme with excellent properties adapted to industrial requirements. Alyw208 classified into the polysaccharide lyase (PL) 7 family showed maximum activity at 35 °C and pH 10.0, indicating its cold-adapted and high-alkaline properties. Furthermore, Alyw208 preserved over 70% of the relative activity within the range of 10–55 °C, with a broader temperature range for the activity compared to other alginate-degrading enzymes with cold adaptation. Recombinant Alyw208 was significantly activated with 1.5 M NaCl to around 2.1 times relative activity. In addition, the endolytic Alyw208 was polyG-preferred, but identified as a bifunctional alginate lyase that could degrade both polyM and polyG effectively, releasing AOs with degrees of polymerization (DPs) of 2–6 and alginate monomers as the final products (that is, DPs 1–6). Alyw208 has been suggested with favorable properties to be a potent candidate for biotechnological and industrial applications. [ABSTRACT FROM AUTHOR]

Eggplant (Solanum melongena L.) is an important economic crop, and to date, there has been no genome-wide identification and analysis of the cyclic nucleotide-gated channel (CNGC) gene family in eggplant. In this study, we identified the CNGC gene family in eggplant, and the results showed that 29 SmCNGC genes were classified into five groups, unevenly distributed across the 12 chromosomes of eggplant. The gene structure and motif analysis indicated that the SmCNGC family proteins may exhibit apparent preferences during evolution. Furthermore, our study revealed the presence of numerous light-responsive elements, hormone-responsive elements, and transcription factor binding sites in the promoter regions of SmCNGC genes, suggesting their significant role in environmental adaptability regulation. Finally, we analyzed the expression patterns of all SmCNGC genes under cold stress and found that SmCNGC1a was significantly upregulated under cold stress. Subcellular localization experiments indicated that this gene is located on the plasma membrane. Subsequently, its importance in the low-temperature response of eggplant was validated through virus-induced gene silencing (VIGS), and its protein interactome was predicted. In summary, our study provides a comprehensive understanding of the function and regulatory mechanisms of the CNGC gene family in eggplant, laying an important foundation for further research on cold adaptation in eggplant. [ABSTRACT FROM AUTHOR]

Bacterial adaptation to cold stress requires wide transcriptional reprogramming. However, the knowledge of molecular mechanisms underlying the cold stress response of mycobacteria is limited. We conducted comparative transcriptomic analysis of Mycobacterium smegmatis subjected to cold shock. The growth of M. smegmatis cultivated at 37 °C was arrested just after exposure to cold (acclimation phase) but later (by 24 h) was resumed at a much slower rate (adaptation phase). Transcriptomic analyses revealed distinct gene expression patterns corresponding to the two phases. During the acclimation phase, differential expression was observed for genes associated with cell wall remodeling, starvation response, and osmotic pressure stress, in parallel with global changes in the expression of transcription factors and the downregulation of ribosomal genes, suggesting an energy-saving strategy to support survival. At the adaptation phase, the expression profiles were recovered, indicating restoration of the processes repressed earlier. Comparison of transcriptional responses in M. smegmatis with those in other bacteria revealed unique adaptation strategies developed by mycobacteria. Our findings shed light on the molecular mechanisms underlying M. smegmatis survival under cold stress. Further research should clarify whether the discovered transcriptional mechanisms exist in other mycobacterial species, including pathogenic Mycobacterium tuberculosis, which could be important for transmission control. [ABSTRACT FROM AUTHOR]

N-glycosylation is a post-translational modification of proteins that occurs across all three domains of life. In Archaea, N-glycosylation is crucial for cell stability and motility, but importantly also has significant implications for virus–host interactions. While some archaeal viruses present glycosylated proteins or interact with glycosylated host proteins, the direct influence of N-glycosylation on archaeal virus–host interactions remains to be elucidated. In this study, we generated an N-glycosylation-deficient mutant of Halorubrum lacusprofundi, a halophilic archaeon commonly used to study cold adaptation, and examined the impact of compromised N-glycosylation on the infection dynamics of two very diverse viruses. While compromised N-glycosylation had no influence on the life cycle of the head-tailed virus HRTV-DL1, we observed a significant effect on membrane-containing virus HFPV-1. Both intracellular genome numbers and extracellular virus particle numbers of HFPV-1 were increased in the mutant strain, which we attribute to instability of the surface-layer which builds the protein envelope of the cell. When testing the impact of compromised N-glycosylation on the life cycle of plasmid vesicles, specialized membrane vesicles that transfer a plasmid between host cells, we determined that plasmid vesicle stability is strongly dependent on the host glycosylation machinery. Our study thus provides important insight into the role of N-glycosylation in virus–host interactions in Archaea, while pointing to how this influence strongly differs amongst various viruses and virus-like elements. [ABSTRACT FROM AUTHOR]

Marine organisms have developed a series of defense and adaptation strategies, permitting them to live and survive in peculiar environments, ranging from temperate to tropical and polar regions, high to low salinity areas and different light conditions, as well as are constantly exposed to variations induced by climate change and human activities. These defense strategies include the production of molecules and enzymes which may have applications for humans as well. In this review, we summarized the studies on bacterial and microalgal polyunsaturated fatty acids, antioxidants, and antifreeze proteins, which can find applications in different market sectors, such as feed and cosmetic fields. For all the aforementioned compounds, the compound annual growth rate is expected to increase by 5.35–36.3% in the near future, as the market interest toward these products is on the rise. Both industries and researchers are focused on developing mechanisms to reduce production time and costs, improve yields, and discover new proteins. [ABSTRACT FROM AUTHOR]

Sheep show characteristics of phenotypic diversity and adaptation to diverse climatic regions. Previous studies indicated associations between copy number variations (CNVs) and climate-driven adaptive evolution in humans and other domestic animals. Here, we constructed a genomic landscape of CNVs (n = 39,145) in 47 old autochthonous populations genotyped at a set of high-density (600 K) SNPs to detect environment-driven signatures of CNVs using a multivariate regression model. We found 136 deletions and 52 duplications that were significantly (Padj. < 0.05) associated with climatic variables. These climate-mediated selective CNVs are involved in functional candidate genes for heat stress and cold climate adaptation (e.g., B3GNTL1, UBE2L3, and TRAF2), coat and wool-related traits (e.g., TMEM9, STRA6, RASGRP2, and PLA2G3), repairing damaged DNA (e.g., HTT), GTPase activity (e.g., COPG), fast metabolism (e.g., LMF2 and LPIN3), fertility and reproduction (e.g., SLC19A1 and CCDC155), growth-related traits (e.g., ADRM1 and IGFALS), and immune response (e.g., BEGAIN and RNF121) in sheep. In particular, we identified significant (Padj. < 0.05) associations between probes in deleted/duplicated CNVs and solar radiation. Enrichment analysis of the gene sets among all the CNVs revealed significant (Padj. < 0.05) enriched gene ontology terms and pathways related to functions such as nucleotide, protein complex, and GTPase activity. Additionally, we observed overlapping between the CNVs and 140 known sheep QTLs. Our findings imply that CNVs can serve as genomic markers for the selection of sheep adapted to specific climatic conditions. [ABSTRACT FROM AUTHOR]

This study reports the complete genome sequence of Subtercola sp. PAMC28395, a strain isolated from cryoconite in Uganda. This strain possesses several active carbohydrate-active enzyme (CAZyme) genes involved in glycogen and trehalose metabolism. Additionally, two specific genes associated with α-galactosidase (GH36) and bacterial alpha-1,2-mannosidase (GH92) were identified in this strain. The presence of these genes indicates the likelihood that they can be expressed, enabling the strain to break down specific polysaccharides derived from plants or the shells of nearby crabs. The authors performed a comparative analysis of CAZyme patterns and biosynthetic gene clusters (BGCs) in several Subtercola strains and provided annotations describing the unique characteristics of these strains. The comparative analysis of BGCs revealed that four strains, including PAMC28395, have oligosaccharide BGCs, and we confirmed that the pentose phosphate pathway was configured perfectly in the genome of PAMC28395, which may be associated with adaptation to low temperatures. Additionally, all strains contained antibiotic resistance genes, indicating a complex self-resistance system. These results suggest that PAMC28395 can adapt quickly to the cold environment and produce energy autonomously. This study provides valuable information on novel functional enzymes, particularly CAZymes, that operate at low temperatures and can be used for biotechnological applications and fundamental research purposes. [ABSTRACT FROM AUTHOR]

SPX-domain proteins (small proteins with only the SPX domain) have been proven to be involved in phosphate-related signal transduction and regulation pathways. Except for OsSPX1 research showing that it plays a role in the process of rice adaptation to cold stress, the potential functions of other SPX genes in cold stress are unknown. Therefore, in this study, we identified six OsSPXs from the whole genome of DXWR. The phylogeny of OsSPXs has a strong correlation with its motif. Transcriptome data analysis showed that OsSPXs were highly sensitive to cold stress, and real-time PCR verified that the levels of OsSPX1, OsSPX2, OsSPX4, and OsSPX6 in cold-tolerant materials (DXWR) during cold treatment were higher than that of cold-sensitive rice (GZX49). The promoter region of DXWR OsSPXs contains a large number of cis-acting elements related to abiotic stress tolerance and plant hormone response. At the same time, these genes have expression patterns that are highly similar to cold-tolerance genes. This study provides useful information about OsSPXs, which is helpful for the gene-function research of DXWR and genetic improvements during breeding. [ABSTRACT FROM AUTHOR]

Temperature changes and periods of detrimental cold occur frequently for many organisms in their natural habitats. Homeothermic animals have evolved metabolic adaptation strategies to increase mitochondrial-based energy expenditure and heat production, largely relying on fat as a fuel source. Alternatively, certain species are able to repress their metabolism during cold periods and enter a state of decreased physiological activity known as torpor. By contrast, poikilotherms, which are unable to maintain their internal temperature, predominantly increase membrane fluidity to diminish cold-related damage from low-temperature stress. However, alterations of molecular pathways and the regulation of lipid-metabolic reprogramming during cold exposure are poorly understood. Here, we review organismal responses that adjust fat metabolism during detrimental cold stress. Cold-related changes in membranes are detected by membrane-bound sensors, which signal to downstream transcriptional effectors, including nuclear hormone receptors of the PPAR (peroxisome proliferator-activated receptor) subfamily. PPARs control lipid metabolic processes, such as fatty acid desaturation, lipid catabolism and mitochondrial-based thermogenesis. Elucidating the underlying molecular mechanisms of cold adaptation may improve beneficial therapeutic cold treatments and could have important implications for medical applications of hypothermia in humans. This includes treatment strategies for hemorrhagic shock, stroke, obesity and cancer. [ABSTRACT FROM AUTHOR]

Alfalfa is conserved in silo-type bunkers in the cold and humid regions of Inner Mongolia, China. Its quality is essential to ensure a healthy and sustainable dairy production. However, the impact of environmental factors on the microbiota and fermentation products of alfalfa silage remains unclear. The present research examined changes in the microbiota and fermentation products and their association with environmental parameters in 72 samples collected from 12 farms located at 4 different latitudes and longitudes across four regions. The samples were labeled with distinct codes, A, B, and C, from the cold–rainy region, D, E, and F, from the warm–rainy region, G, H, and I from the cold–dry region, and J, K, and L from the warm–dry region. The lactic acid levels ranged from 14.25 to 24.27 g/kg of DM across all samples. The pH and concentrations of NH3-N and butyric acid in samples A, B, and H were higher (p < 0.01) than in the other samples. Samples D and E had higher acetic acid concentrations and 1, 2-propanediol content (p < 0.01). The fresh material was dominated by Pantoea and Pseudomonas, whereas Lactobacillus was the most dominant genus in all silages, except for the B silage. The A, B, and H silages contained more Clostridium but less Lactobacillus than the other silages. The lactic acid levels were strongly associated with Lactobacillus plantarum, Weissella paramesenteroides, Lactobacillus acetotolerans, Pedobacter borvungensis, and Lactobacillus brevis (p < 0.01). In contrast, the pH and the NH3-N and butyric acid concentrations were strongly associated (p < 0.01) with the presence of Clostridium estertheticum. A correlation analysis revealed that precipitation, temperature, longitude, and latitude were the most critical factors influencing epiphytic microbes in the fresh material. After silage fermentation, low-temperature conditions significantly affected the fermentation products and microbial community composition. In conclusion, the microbial community of silages is distinctive in cold and humid regions, and climatic parameters ultimately affect the microbiota and fermentation products. Furthermore, the findings of this study demonstrate that Illumina MiSeq sequencing combined with environmental factor assessment might provide new information about the microbiota composition and fermentation quality of silages, facilitating the achievement of high-quality silage. [ABSTRACT FROM AUTHOR]

Simple Summary: Whole-genome SNP data from 613 Chinese indigenous pigs were collected to comprehensively estimate the genetic diversity, genetic relationship, and population genetic structure of the indigenous pig meta-populations. These Chinese meta-populations were characterized by genetic distance, genetic difference index, and runs of homozygosity (ROH). The contribution of genetic diversity of each meta-population was scaled based on genetic and allelic diversity, which provides a basis for improving the conservation project. Further, a selective sweep analysis revealed that genes related to fat deposition and heat stress may contribute to the adaptability of the indigenous pigs to cold and heat. These findings provide a theoretical basis for the improvement of conservation strategies and insights into the environmental adaptability of Chinese indigenous pigs. The diversification of indigenous pig breeds in China has resulted from multiple climate, topographic, and human cultural influences. The numerous indigenous pig breeds can be geographically divided into six meta-populations; however, their genetic relationships, contributions to genetic diversity, and genetic signatures remain unclear. Whole-genome SNP data for 613 indigenous pigs from the six Chinese meta-populations were obtained and analyzed. Population genetic analyses confirmed significant genetic differentiation and a moderate mixture among the Chinese indigenous pig meta-populations. The North China (NC) meta-population had the largest contribution to genetic and allelic diversity. Evidence from selective sweep signatures revealed that genes related to fat deposition and heat stress response (EPAS1, NFE2L2, VPS13A, SPRY1, PLA2G4A, and UBE3D) were potentially involved in adaptations to cold and heat. These findings from population genetic analyses provide a better understanding of indigenous pig characteristics in different environments and a theoretical basis for future work on the conservation and breeding of Chinese indigenous pigs. [ABSTRACT FROM AUTHOR]

Piglets are susceptible to cold, and piglet death caused by cold stress leads to economic losses in the pig industry in cold areas. Skeletal muscle plays a key role in adaptive thermogenesis in mammals, but the related mechanism in pigs is unclear. In this study, cold-tolerant Tibetan pigs and cold-sensitive Bama pigs were subjected to either a cold environment (4 °C) or a room temperature environment (25 °C) for 3 days. The biceps femoris (BF) and longissimus dorsi muscle (LDM) were collected for phenotypic analysis, and the BF was used for genome-wide transcriptional profiling. Our results showed that Tibetan pigs had a higher body temperature than Bama pigs upon cold stimulation. RNA-seq data indicated a stronger transcriptional response in the skeletal muscle of Tibetan pigs upon cold stimulation, as more differentially expressed genes (DEGs) were identified with the same criteria (p < 0.05 and fold change > 2). In addition, distinct pathway signaling patterns in skeletal muscle upon cold exposure were found between the breeds of pigs. Mitochondrial beta-oxidation-related genes and pathways were significantly upregulated in Tibetan pigs, indicating that Tibetan pigs may use fatty acids as the primary fuel source to protect against cold. However, the significant upregulation of inflammatory response- and glycolysis-related genes and pathways in the skeletal muscle of Bama pigs suggested that these pigs may use glucose as the primary fuel source in cold environments. Together, our study revealed the distinct transcriptional responses of skeletal muscle to cold stimulation in Tibetan pigs and Bama pigs and provided novel insights for future investigation of the cold adaptation mechanism in pigs. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs (lncRNAs) have been shown to play critical regulatory roles in plants. Ammopiptanthus nanus can survive under severe low-temperature stress, and lncRNAs may play crucial roles in the gene regulation network underlying the cold stress response in A. nanus. To investigate the roles of lncRNAs in the cold stress response of A. nanus, a combined lncRNA and mRNA expression profiling under cold stress was conducted. Up to 4890 novel lncRNAs were identified in A. nanus and 1322 of them were differentially expressed under cold stress, including 543 up-regulated and 779 down-regulated lncRNAs. A total of 421 lncRNAs were found to participate in the cold stress response by forming lncRNA–mRNA modules and regulating the genes encoding the stress-related transcription factors and enzymes in a cis-acting manner. We found that 31 lncRNAs acting as miRNA precursors and 8 lncRNAs acting as endogenous competitive targets of miRNAs participated in the cold stress response by forming lncRNA–miRNA–mRNA regulatory modules. In particular, a cold stress-responsive lncRNA, TCONS00065739, which was experimentally proven to be an endogenous competitive target of miR530, contributed to the cold stress adaptation by regulating TZP in A. nanus. These results provide new data for understanding the biological roles of lncRNAs in response to cold stress in plants. [ABSTRACT FROM AUTHOR]

Dry fermented sausage innovation trends are linked to consumer preferences for clean label and sodium-reduced foods. This study aims to evaluate the effect of the formulation and production process temperature on the dynamics of bacterial communities in fuet-type dry fermented sausages using metataxonomics. Six fuet batches were manufactured, including formulations without and with the addition of nitrifying salts (replaced or not by pork liver auto-hydrolysate as a colouring agent), processed at 3 to 12 °C, and a partial replacement of NaCl by KCl, processed at 12 °C. Fermentation was performed spontaneously or by a starter culture. Physicochemical characterisation and culture-dependent and independent bacterial analyses were performed at day 0, 4 and 12, at the end of ripening (aw < 0.90) and after storage. Temperature was the most important factor determining the change in pH, aw and lactic acid bacteria levels while the presence of a starter culture promoted a pH decrease. Metataxonomic analysis showed that low temperature processes and the absence of nitrifying salts allowed the growth of spoilage-related species, while sausages submitted to a mild temperature containing a starter culture and nitrifying salts showed less bacterial diversity. Liver auto-hydrolysate added putative probiotic species to the product. This study provides valuable information to manufacturers who want to innovate safely. [ABSTRACT FROM AUTHOR]