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Spike density and processing quality are important traits in modern wheat production and are controlled by multiple gene loci. The associated genes have been intensively studied and new discoveries have been constantly reported during the past few decades. However, no gene playing a significant role in the development of these two traits has been identified. In the current study, a common wheat mutant with extremely compact spikes and good processing quality was isolated and characterized. A new allele ( Q c1 ) of the Q gene (an important domestication gene) responsible for the mutant phenotype was cloned, and the molecular mechanism for the mutant phenotype was studied. Results revealed that Q c1 originated from a point mutation that interferes with the miRNA172-directed cleavage of Q transcripts, leading to its overexpression. It also reduces the longitudinal cell size of rachises, resulting in an increased spike density. Furthermore, Q c1 increases the number of vascular bundles, which suggests a higher efficiency in the transportation of assimilates in the spikes of the mutant than that of wild type. This accounts for the improved processing quality. The effects of Q c1 on spike density and wheat processing quality were confirmed by analyzing nine common wheat mutants possessing four different Q c alleles. These results deepen our understanding of the key roles of Q gene, and provide new insights for the potential application of Q c alleles in wheat quality breeding., (Copyright © 2018 Xu et al.)

This study aimed to explore mixed-species biofilm formation (BF) between meat-derived Escherichia coli and Pseudomonas. The biofilm-forming capacity of isolates was evaluated by means of microplate crystal violet staining and the process of mixed-species biofilm formation between representative strains was investigated. The dynamic changes of biofilm amount, microstructure and the composition of extracellular polymeric substances (EPS) were examined. Absolute quantitative real-time PCR was used to analyze the difference in the expression of BF-related genes. The results showed that there were significant inter-strain differences in the biofilm-forming capacity of E. coli and Pseudomonas (P < 0.05), in which the strains with strong biofilm-forming capacity accounted for 25.81% and 23.08%, respectively. The results of plate counting showed that the BF processes of E. coli D4-18 + Pseudomonas Y2-2 10, and E. coli C-13 + Pseudomonas Y2-1 1 were different on stainless steel sheet, and the interaction between the two species changed with BF time. Similar changes in the microstructure were observed by confocal laser scanning microscope (CLSM). The secretion of protein and polysaccharide in EPS was inhibited during mixed-species BF; the amount of protein decreased by 31% and 48%, respectively, and the amount of polysaccharide decreased by 38% and 56%, respectively, at 72 and 168 h of culture compared with the total EPS of the two single-species biofilms. The results of gene expression per unit cell number showed that the expression of BF-related genes was significantly up-regulated in the biofilm compared with the planktonic cells (P < 0.05). Compared with the single-species biofilm, the papC and csgA genes of E. coli in the mixed biofilm were significantly up-regulated at 72 and 168 h (P < 0.01), while the phoR and cbrA genes of Pseudomonas were significantly down-regulated at 72 h (P < 0.01). The absolute amount of genes expression per unit area in mixed-species BF changed compared with that in single-species BF. This study can provide a scientific basis for understanding the mixed-species BF of meat-derived spoilage microorganisms and for the risk assessment and control of microbial contamination in meat production and processing.

The aim of the experiment was to investigate the effect of Chinese herbal compound additive on growth performance, serum biochemical indices and spleen IL-2 mRNA expression of Hy-line Brown egg chicks. A total of 960 one-day-old healthy Hy-line Brown egg chicks were randomly divided into two groups with five replicates per group and 96 chickens per replicate. Egg chicks in control group were fed with basal diet, and those in experimental group were fed with basal diet supplemented with 0.2% Chinese herbal compound additive. The experiment lasted for 42 d. The results showed that compared with control group, the final weight and average daily gain of egg chicks in experimental group were extremely increased (P<0.01), and the feed to gain ratio and mortality rate were extremely decreased (P<0.01). Compared with control group, keel length and tibia length of egg chicks in experimental group were extremely increased (P<0.01), and chest width and hip width were significantly increased (P<0.05). Compared with control group, the content of BUN and TC in serum of egg chicks in experimental group were extremely decreased (P<0.01), the activity of AST was significantly decreased (P<0.05), and the content of IFN-γ and IL-2 were extremely increased (P<0.01). Compared with control group, thymus index, bursa of Fabricius index and spleen IL-2 mRNA expression of egg chicks in experimental group were extremely increased (P<0.01). The study indicates that 0.2% Chinese herbal compound additive in the diet can improve the growth performance, improve the serum biochemical indexes, and promote the development of immune organs and the expression of IL-2 mRNA in spleen of Hy-line Brown egg chicks. [ABSTRACT FROM AUTHOR]

Type 2C protein phosphatases (PP2Cs) play key roles in regulating plant senescence and ripening. Here, we discovered a subfamily F PP2C, SlPP2C, associated with leaf senescence through transcriptome analysis. The gene expression, protein accumulation, and promoter activity of SlPP2C all gradually increased along with the progression of leaf and flower senescence and fruit ripening in tomato. Also, the expression of SlPP2C was highly up‐regulated by the senescent‐inducible hormone treatments, showing more sensitivity to ethylene (ETH) and abscisic acid (ABA). Meanwhile, SlPP2C RNA interference (RNAi) tomato transgenic lines showed obvious delayed senescence and ripening phenotypes of leaves, flowers, and fruits. SlPP2C RNAi lines delayed leaf senescence with higher chlorophyll fluorescence and content, and lower expressions of senescence marker genes (SlSGR1 and SlSAG12) compared to WT. SlPP2C RNAi lines clearly delayed flower senescence time; it was at least twice longer than WT. SlPP2C RNAi lines delayed fruit ripening, exhibiting higher firmness and lower polygalacturonase activity compared to WT. In addition, we proved that SlPP2C is unable to interact with any of the ABA receptors (SlPYLs). Together, the results demonstrate that SlPP2C is a senescence‐related and ripening‐related gene. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Heat stress often occurs in the modern poultry industry, which impairs growth performance, particularly via reducing appetite. This study was aimed to investigate the mechanism of attenuating appetite by chronic heat exposure in broilers. A total of 144 broilers (28 days old) were allocated to normal control (NC, 22 °C), heat stress (32 °C), and pair‐fed (22 °C) groups. RESULTS: Chronic heat exposure significantly increased cloacal temperatures and respiration rates, decreased the average daily feed intake and average daily gain, increased feed‐to‐gain ratio compared with the NC group, and elevated the concentrations of ghrelin and cholecystokinin (CCK) both in serum and intestine, as well as peptide YY and somatostatin in intestine on 35‐ or 42‐day‐old broilers. Moreover, heat exposure decreased villi height (VH) and the ratio of VH to crypt depth (CD), while it increased CD in the jejunum on 35‐ and 42 day‐olds, increased (P < 0.05) the concentrations of valine and isoleucine in plasma on 42 days, and upregulated (P < 0.05) the expression of taste receptor type 1 members 1 and 3 (T1R1 and T1R3), CCK, and ghrelin in the intestine on 35‐ or 42‐day‐old broilers. CONCLUSION: Chronic heat exposure impairs the performance, intestinal morphology and appetite, which may be correlated with the increased secretion or gene expression of appetite‐related hormones and genes, and the higher expression of nutrient‐sensing receptors (T1R1 and T1R3) in broilers. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Cytokinin oxidases/dehydrogenases (CKXs) are the only known enzymes that specifically catalyze the degradation of cytokinins (CKs). CKXs regulate CK levels in plants and play an essential role in CK regulatory processes. In spite of their physiological importance, systematic analyses of CKX genes in woodland strawberry, Fragaria vesca , have not been performed yet. In this paper, we report a genome-wide identification and characterization of FvCKX genes. A total of eight FvCKX genes were identified. Phylogenetic analysis showed that species-specific expansion of FvCKX genes have occurred, possibly through segmental duplication or single gene transposition-duplication. Various types of cis-elements detected in the promoters suggested a functional diversification of the FvCKX genes. Quantitative PCR assays were carried out, demonstrating differential expression patterns of FvCKX genes in the organs, under abiotic stresses including drought, salt and heat, and under abscisic acid (ABA) treatments. Most expressed FvCKX s exhibited relatively high expression in roots, stolons, leaves, flowers and young fruits. Significant induction of FvCKX genes was observed in leaves and roots under salt treatment, and in leaves under drought and ABA treatments, suggesting that CKs were negative regulators in strawberry responses to drought, salt and ABA. More FvCKX genes were repressed after heat treatment, indicating a possible different pattern of CK modulation under heat. Taken together, our results show moderate expansion and diverse expression patterns of FvCKX genes in woodland strawberry. This will help to enhance the understanding of functional divergence of these FvCKX genes and provide a basis for improving stress tolerance of strawberries by manipulating the CK content. [ABSTRACT FROM AUTHOR]

Abstract: Half-smooth tongue sole, Cynoglossus semilaevis, is an ideal model to investigate the regulatory mechanisms of sexual growth dimorphism in fish species. The aim of the study was to investigate the effect of differential age of sexual maturity for females and males on growth and GH mRNA expression in C. semilaevis. The body weight differences between the sexes were not significant in C. semilaevis at age 5months when females and males were all immature. Significant differences in body weight between the sexes were found after early sexual maturation of males at the age of 9months. The body weight of 21-month-old females (621.4±86.4g), still not immature, was even 3.28 times higher than that of the males (189.7±14.4g). The cDNAs encoding GH in C. semilaevis was cloned. The GH gene is 2924bp long and consists of six exons and five introns. The results of qRT-PCR showed that GH mRNA levels of the immature females were not significantly different from that of immature males at age 5months. However, GH mRNA levels of the immature females were significantly higher compared with those of the mature males at age 9months (P<0.05). At age 11months, GH mRNA levels of females were even 6.4-fold higher than that of males. In conclusion, for the first time we show that early sexual maturity of males is the main cause of sexual growth dimorphism in C. semilaevis and exert significant effect on GH mRNA expression. [Copyright &y& Elsevier]

mibnn2002, found from an allele screen, showed early segmentation defect and severe cell death phenotypes, which are different from previously known mib mutants. Despite distinct morphological phenotypes, the typical mib molecular phenotypes: her4 down-regulation, neurogenic phenotype and cold sensitive dlc expression pattern, still remained. The linkage analysis also indicated that mibnn2002 is a new mib allele. Failure of specification in anterior 7-10 somites is likely due to lack of foxc1a expression in mibnn2002 homozygotes. Somites and somite markers gradually appeared after 7-10 somite stage, suggesting that foxc1a is only essential for the formation of anterior 7-10 somites. Apoptosis began around 16-somite stage with p53 up-regulation. To find the possible links of mib, foxc1a and apoptosis, transcriptome analysis was employed. About 140 genes, including wnt3a, foxc1a and mib, were not detected in the homozygotes. Overexpression of foxc1a mRNA in mibnn2002 homozygotes partially rescued the anterior somite specification. In the process of characterizing mibnn2002 mutation, we integrated the scaffolds containing mib locus into chromosome 2 (or linkage group 2, LG2) based on synteny comparison and transcriptome results. Genomic PCR analysis further supported the conclusion and showed that mibnn2002 has a chromosomal deletion with the size of about 9.6 Mbp. [ABSTRACT FROM AUTHOR]

With the wide application of RNA-Seq technology, thousands of circular RNAs (circRNAs) have been identified in different type of tissues and cells in many organisms, but little is known on the human aortic valve expressed circRNAs. In this study, we identified all circRNAs in two calcified human aortic valves, and characterized the features of all circRNAs. A total of 5476 circRNAs were identified in human aortic valves, including 1412 (25.79%) aortic valve specific circRNAs. Next, we showed that most aortic valve specific circRNAs were derived from the exonic regions of their host genes, and majority of the host genes contained less than three circRNAs. To predict the potential function of aortic valve specific circRNAs, we performed the GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis for the host genes, and identified both microRNA (miRNA) and RNA binding protein (RBP) binding sites inside aortic valve specific circRNAs. Results showed that these host genes were involved in some aortic valve related function pathways, such as ECM-receptor interaction pathway, ErbB signaling pathway, and vascular smooth muscle contraction pathway. We also found that most aortic valve specific circRNAs harbored abundant miRNA response elements (MREs), and some aortic valve specific circRNAs could bind to RBP of interest. Functional analysis suggested that these aortic valve specific circRNAs could act as post-transcriptional regulators. [ABSTRACT FROM AUTHOR]

Examines the interaction between the Schizosaccharomyces pombe (sp) autonomously replicating sequence 1 and the sp origin recognition complex (spORC). Effect of origin recognition complex on the initiation of DNA replication; DNA binding properties of spORC; Mechanism used by sp to recognize its origins different from that used by Saccharomyces cerevisiae.

Studies have demonstrated that chronic heat stress can accelerate glycolysis, decrease glycogen content in muscle, and affect muscle quality. However, the consequences of chronic heat stress on glycogen synthesis, miRNA expression in pectoralis major (PM) muscle, and its regulatory functions remain unknown. In this study, high-throughput sequencing and cell experiments were used to explore the effects of chronic heat stress on miRNA expression profiles and the regulatory mechanisms of miRNAs in glycogen synthesis under chronic heat stress. In total, 144 cocks were allocated into 3 groups: the normal control (NC) group, the heat stress (HS) group, and the pair-fed (PF) group. In total, 30 differently expressed (DE) miRNAs were screened after excluding the effect of feed intake, which were mainly related to metabolism, signal transduction, cell growth and death. Furthermore, the gga-miR-212-5p/ GYS1 axis was predicted to participate in glycogen synthesis through the miRNA-mRNA analysis, and a dual-luciferase reporter test assay confirmed the target relationship. Mechanistically, chronic heat stress up-regulated gga-miR-212-5p, which could inhibit the expression of GYS1 in the PM muscle. Knocking down gga-miR-212-5p alleviates the reduction of glycogen content caused by chronic heat stress; overexpression of gga-miR-212-5p can reduce glycogen content. This study provided another important mechanism for the decreased glycogen contents within the PM muscle of broilers under heat stress, which might contribute to impaired meat quality. [ABSTRACT FROM AUTHOR]

Abstract: Pituitary adenylate cyclase activating polypeptide (PACAP) and growth hormone-releasing hormone (GHRH) are regulators of growth hormone secretion. In this article, we examined the difference in growth and mRNA expression of PACAP and GHRH between the sexes in half-smooth tongue sole, an important cultured fish species indicating sexually growth dimorphism in China. Firstly, a significant body weight difference between females and males was first observed at 7months (P <0.05) and at 18months the mean body weight of the females (771.0±44.3g) was as much as 4.9 times higher than that of males (130.6±6.0g). As a result, half-smooth tongue sole, Cynoglossus semilaevis, is a good model to investigate the effects of growth-related genes expression on sexual growth dimorphism. Secondly, the cDNAs encoding PRP/PACAP and GHRH were isolated. Two differently processed mRNA transcripts of PRP/PACAP (PRP-encoding and PRP splice variant) were found. PACAP and GHRH mRNA was highly abundant in brain and less abundant in other tissues. However, PACAP mRNA was expressed in most brain regions, and was lower in the cerebellum. GHRH mRNA was predominantly expressed in the hypothalamus and weakly expressed in all areas of the brain examined. Ontogenetic expression analysis indicated that PACAP and GHRH mRNA was detected in the early stages of embryogenesis. Finally, differential expression showed that there was no significant difference of the expression level of PACAP or GHRH between the sexes before 8months of age. However, between 9 and 12months of age, the GHRH mRNA expression level in males was significantly higher than in females (P <0.05), which might be associated with GH deficiency in males. In contrast, the male PACAP mRNA expression level was not significantly higher than that in females even at 9 and 12months of age. The present results provide important clues for understanding the sexual growth dimorphism mechanisms in half-smooth tongue sole. [ABSTRACT FROM AUTHOR]

This study was aimed to elucidate effects of taurine supplementation on growth performance, jejunal histology, and appetite-related genes expressions of broilers under heat stress. A total of 144 broilers on 28 d were allocated to three groups with 6 cages each group, 8 broilers per cage. The experiment period is from 28 to 42 d of age. In normal control (NC) group, chickens were held at 22°C ambient temperature (thermoneutral) and fed a basal diet. In the heat stress (HS) group, chickens were raised to constant HS at 32°C and received a basal diet. In the HS+ taurine group, chickens were fed a basal diet with 5 g/kg taurine supplementation. The results showed that HS group had lower average daily feed intake, average daily gain, higher feed/gain ratio compared with the NC group (P < 0.05), while taurine addition did not ameliorate the lowered growth performance. Cloacal temperatures and respiration rates in the HS and heat taurine group were higher (P < 0.05) than in the NC group. Heat stress treatment elevated (P < 0.05) the concentrations of ghrelin and cholecystokinin (CCK) in serum and intestine, together with peptide YY and somatostatin (SS) in the intestine after 7 or 14 d of heat exposure. In addition, HS damaged the jejunal morphology by shortening villus height and deepening crypt depth (P < 0.05), upregulated (P < 0.05) the mRNA expression of taste receptor type 1 member 1 (T1R1), taste receptor type 1 member 3 (T1R3), CCK and ghrelin in the intestine. Taurine supplementation significantly mitigated the impairment of jejunal morphology, decreased the concentrations of serum ghrelin, increased the concentrations of somatostatin and peptide YY in the duodenum, elevated the mRNA expression levels of CCK in the jejunum compared with the HS group. In conclusion, taurine exerted no positive effects on the growth performance, while mitigated the impairment of jejunal morphology, increased some anorexic hormones secretion and mRNA expression of appetite-related genes in the intestine of broilers subjected to HS. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7 and Pseudomonas were considered as common colonizers of fresh and spoilage meat, where they tended to live in the proximity. In this study, we tested the interplay between different isolates of E. coli O157:H7 and Pseudomonas in random two-by-two combinations grown as dual-species consortia. Results showed that the growth fitness of E. coli was not facilitated by the presence of all tested Pseudomonas strains, and vice versa. Representative combinations were further selected to investigate the property changes following the time course of biofilms formation as compared to single species. Cell counting confirmed that the growth of E. coli O157:H7 was challenged by the presence of Pseudomonas strains as previously described. Our findings shed new light on the evidence that the pathogenicity of E. coli O157:H7 was negatively affected by the presence of Pseudomonas according to the evaluation of spatial organization and genetic expression of virulence factors, which might be a naturally existing biological phenomenon constraining the safety risk of former strains in meat processing and preservation. Intriguingly, we observed that E. coli managed to stably co-exist at low cellular abundance in the progress of dual-species consortia, indicating successful adaptive mechanisms that need further investigations to uncover. • The interplay between different isolates of E. coli O157:H7 and Pseudomonas. • E. coli O157:H7 managed to stably co-exist at low biomass in dual-species biofilm. • Virulence genes expression in E. coli O157:H7 was reduced by Pseudomonas. [ABSTRACT FROM AUTHOR]

• Showing an antagonistic effect of B. methylotrophicus on I. robusta. • Sequencing the genome of biocontrol B. methylotrophicus. • Exploring the DEGs of B. methylotrophicus in interaction of bacterial-fungal. • Revealing the molecular response pattern of B. methylotrophicus to I. robusta. To explain the molecular mechanism of the biocontrol exerted by Bacillus methylotrophicus NJ13 against Ilyonectria robusta , this study mainly focused on the following aspects. (i) Background: I. robusta is a dominant species of soil-borne pathogen causing ginseng rusty root rot. The ginseng endophytic bacteria B. methylotrophicus NJ13 can effectively inhibit the growth of I. robusta DQX01 and control the disease. (ii) Methods: Through in vitro antagonism experiments and microscopic observation, the inhibitory effect of the strain NJ13 against strain DQX01 was determined. The whole genome of NJ13 was sequenced by using the Illumina NovaSeq PE150 platform, and the gene expression pattern of NJ13 against DQX01 was revealed by using RNA-seq. (iii) Results: NJ13 could significantly inhibit the growth of DQX01, leading to the mycelial and conidia of DQX01 appearing abnormal and swollen. The genome of NJ13 consists of a circular chromosome of 3,929,584 bp, with 4024 coding DNA sequences (CDSs). The number of NJ13 differentially expressed genes (DEGs) (| log2 (fold change) | > 1, q < 0.005) was 691, of which 233 were upregulated and 458 downregulated. (iv) Conclusions: According to both in vivo and in vitro experiments, NJ13 shows good antagonistic activity against DQX01. Secondary metabolite gene clusters probably regulate the good antagonistic effect, as demonstrated through the analysis of strain NJ13′s genome. When the strain NJ13 interacted with DQX01, a defensive response within B. methylotrophicus NJ13 was triggered. The transcriptomic profiling of NJ13 could provide an explanation for this phenomenon. [ABSTRACT FROM AUTHOR]

Treacher Collins Syndrome (TCS) is a rare congenital birth disorder (1 in 50,000 live births) characterized by severe craniofacial defects, including the downward slanting palpebral fissures, hypoplasia of the facial bones, and cleft palate (CP). Over 90% of patients with TCS have a mutation in the TCOF1 gene. However, some patients exhibit mutations in two new causative genes, POLR1C and POLR1D , which encode subunits of RNA polymerases I and III, that affect ribosome biogenesis. In this study, we examine the role of POLR1C in TCS using zebrafish as a model system. Our data confirmed that polr1c is highly expressed in the facial region, and dysfunction of this gene by knockdown or knock-out resulted in mis-expression of neural crest cells during early development that leads to TCS phenotype. Next generation sequencing and bioinformatics analysis of the polr1c mutants further demonstrated the up-regulated p53 pathway and predicted skeletal disorders. Lastly, we partially rescued the TCS facial phenotype in the background of p53 mutants, which supported the hypothesis that POLR1C-dependent type 3 TCS is associated with the p53 pathway. [ABSTRACT FROM AUTHOR]

Abstract: Interleukin 18 (IL-18) is a proinflammatory cytokine with an ability to accelerate cell proliferation through activating other factors. However, little is yet understood of the role of IL-18 in the regulation of liver regeneration (LR). To study the effect of IL-18 on LR, the gene expression profiles of hepatocytes isolated from rat regenerative liver were determined by Rat Genome 230 2.0 microarray. Next, the synergistic effects of genes associated to IL-18 pathway were analyzed by expression profile function Et. Then, the expression level of IL-18 was examined by RT-PCR and ELISA. Finally, the effect of IL-18 on hepatocyte proliferation was detected by injecting recombinant rat IL-18 (rrIL-18) into rats immediately after partial hepatectomy (PH) and the rate of hepatocyte proliferation was detected by BrdU labeling. The microarray result showed that the expressions of 13 genes of IL-18 pathway and 49 cell proliferation genes regulated by the pathway were significantly altered at transcriptional level. The Et values of three branches of IL-18 pathway, NF-κB, p38 and JNK, were markedly enhanced during the priming and progressing phases of rat LR. The mRNA level of IL-18 was significantly elevated at 2 and 36h, and its level in plasma was also significantly increased at 2h, and reached the peaks at 12h and 48h after PH (p <0.05). The number of BrdU positive cells was dramatically increased in rats treated with IL-18 compared to PBS control group (p <0.01). In conclusion, IL-18 promotes rat hepatocyte proliferation in the LR priming and progressing phases after PH. [Copyright &y& Elsevier]

mibnn2002, found from an allele screen, showed early segmentation defect and severe cell death phenotypes, which are different from previously known mib mutants. Despite distinct morphological phenotypes, the typical mib molecular phenotypes: her4 down-regulation, neurogenic phenotype and cold sensitive dlc expression pattern, still remained. The linkage analysis also indicated that mibnn2002 is a new mib allele. Failure of specification in anterior 7-10 somites is likely due to lack of foxc1a expression in mibnn2002 homozygotes. Somites and somite markers gradually appeared after 7-10 somite stage, suggesting that foxc1a is only essential for the formation of anterior 7-10 somites. Apoptosis began around 16-somite stage with p53 up-regulation. To find the possible links of mib, foxc1a and apoptosis, transcriptome analysis was employed. About 140 genes, including wnt3a, foxc1a and mib, were not detected in the homozygotes. Overexpression of foxc1a mRNA in mibnn2002 homozygotes partially rescued the anterior somite specification. In the process of characterizing mibnn2002 mutation, we integrated the scaffolds containing mib locus into chromosome 2 (or linkage group 2, LG2) based on synteny comparison and transcriptome results. Genomic PCR analysis further supported the conclusion and showed that mibnn2002 has a chromosomal deletion with the size of about 9.6 Mbp. [ABSTRACT FROM AUTHOR]