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Cyclin-dependent kinase (CDK), the pivotal controller of cell cycle progression, is involved in stress resistance and plant growth. Moso bamboo (Phyllostachys edulis) with surprisingly rapid growth depends on continuous cell division, but the CDK gene family information is still lacking. Here, we performed the systematic identification and analysis of the CDK genes in moso bamboo. 40 PeCDK genes were identified and divided into eight subgroups via phylogeny. The same subgroup possessed extremely conserved sequences and similar gene structure. In addition, evolutionary analysis suggested that the PeCDK gene family may have experienced extensive duplication events primarily 6.85–13.71 million years ago (MYA), with segmental duplication dominating. Furthermore, the multiple promoter cis-elements determined in PeCDK genes indicated their potential functions. The expression patterns revealed that most PeCDK genes participated in responses to drought, salt, ABA and SA signals, cell wall synthesis, organ developmental processes and callus growth. The insights gained provide beneficial reference for clarifying the functions of PeCDKs as well as exploring the growth mechanism in bamboo. [ABSTRACT FROM AUTHOR]

Mirabilis himalaica is a traditional Tibetan medicinal plant in China. However, it has become a class I endangered medicinal plant. Therefore, the utilization of M. himalaica callus to propagate germplasm resources is of great significance. Numerous active compounds have been found in M. himalaica, most of which have been isolated from phenolic acids. In this study, UV-B radiation enhanced the accumulation of phenolic acids effectively in M. himalaica callus. The multi-omics profiles were used to reveal the co-expression regulated patterns of genes related to phenolic acid synthesis in UV-B treated M. himalaica callus. In this way, 8 medicinal metabolites were identified, including rosmarinic acid, sinapic acid, coniferin, salicylic acid, tyrosol, isochlorogenic acid A, isochlorogenic acid B and isochlorogenic acid C. The transcriptome data were divided into 26 modules based on similar expression pattern by using the weighted gene correlation network analysis (WGCNA). It revealed that MEturquoise module correlated with above eight target metabolites. Eventually, 11 structural genes and 31 transcription factors related to phenolic acid biosynthesis were screened. Subsequently, co-expression network was constructed between these genes, transcription factors and metabolites, among which PAL, CAD and CYP73A had strong co-expression relationship with above eight target metabolites. Transcription factors such as MYB, bHLH, bZIP, PLATZ, AP2/ERF-ERF73, WRKY33 and WRKY42 had strong co-expression relationship with eight target metabolites. Consequently, these findings indicated that UV-B treated callus is a cost-efficient alternative to wild M. himalaica, which is valuable for the use of this endangered plant.Key message: Phenolic acid content in Mirabilis himalaica callus was increased by UV-B treatment and the biosynthesis of phenolic acid is initiated by phenylpropanoid pathway and tyrosine-derived pathway. [ABSTRACT FROM AUTHOR]

In order to obtain the inorganic efficient antibacterial agents, the means of ion doping and morphology construction in this research are used to enhance the antibacterial property of nano-MgO, which is according to the "oxidative damage mechanism" and "contact mechanism". In this work, the nano-textured Sc2O3-MgO are synthesized by doping Sc3+ in nano-MgO lattice through calcining at 600 °C. When the Sc3+ content reaches 10%, the nanotextures on the powders surface are pretty clearly visible and uniform, and the specific surface area and the oxygen vacancy are ideal, so that the 10% Sc3+-doped powders (SM-10) has the excellent antibacterial property against E. coli and S. aureus (MBC = 0.03 mg/mL). The efficient antibacterial agents in this research have a better antibacterial effect than the 0% Sc3+-doped powders (SM-0, MBC = 0.20 mg/mL) and the commercial nano-MgO (CM, MBC = 0.40 mg/mL), which have application prospects in the field of antibacterial. [ABSTRACT FROM AUTHOR]

The investigation was aimed at evaluating the metallurgical and mechanical properties of high-speed fiber laser welded thick Q890 high strength low alloy (HSLA) steel with varying weld geometries instead of multi-layer multi-pass electric arc welding which led to the low machining efficiency and produced multiple sandwich structures in welding joints. 16 mm thick Q890 low alloy high strength steel plate was conducted based 2.5 and 5 mm gap size, respectively. The results showed that the size of hardening and softening zone was reduced by lower heat input laser welding with filling metal. The average width of HAZ was 1.2 mm in 2.5 gap and 1.9 mm in 5 mm gap. The maximum hardness was 485 HV and 482 HV and the minimum was 323 HV and 333 HV, respectively. The average width of softening zone was 0.8 mm and minimum hardness was 323 HV. The tensile properties could meet the standard requirement. The elongation rate was 10.4 and 7.6%, respectively, in 2.5 and 5 mm gap. The Charpy impact energy values of HAZ were 13.48 and 12.97 J, respectively. The weld seam was 21.11 and 16.09 J separately. Comparably, the profile of weld seam was better in 2.5 mm gap size. [ABSTRACT FROM AUTHOR]

The H5N8 avian influenza viruses have been widely circulating in wild birds and are responsible for the loss of over 33 million domestic poultry in Europe, Russia, Middle East, and Asia since January 2020. To monitor the invasion and spread of the H5N8 virus in China, we performed active surveillance by analyzing 317 wild bird samples and swab samples collected from 41,172 poultry all over the country. We isolated 22 H5N8 viruses from wild birds and 14 H5N8 viruses from waterfowls. Genetic analysis indicated that the 36 viruses formed two different genotypes: one genotype viruses were widely detected from different wild birds and domestic waterfowls; the other genotype was isolated from a whopper swan. We further revealed the origin and spatiotemporal spread of these two distinct H5N8 virus genotypes in 2020 and 2021. Animal studies indicated that the H5N8 isolates are highly pathogenic to chickens, mildly pathogenic in ducks, but have distinct pathotypes in mice. Moreover, we found that vaccinated poultry in China could be completely protected against H5N8 virus challenge. Given that the H5N8 viruses are likely to continue to spread in wild birds, vaccination of poultry is highly recommended in high-risk countries to prevent H5N8 avian influenza. [ABSTRACT FROM AUTHOR]

The basic helix-loop-helix (bHLH) proteins GL3 (GlABRA 3) and EGL3 (Enhancer of GLABRA 3) are transcription factors that establish physical interactions with GL1 and TTG1 to regulate trichome development in Arabidopsis. In this study, we identified GL3 and EGL3 homologous genes from Rosa roxburghii, named RrGL3 and RrEGL3, respectively. RrGL3 and RrEGL3 were both exclusively localized in the nucleus. Transcriptional profiling and in situ hybridization demonstrated that the expression level of RrEGL3 was significantly higher than RrGL3 in vegetative and reproductive tissues. Moreover, RrEGL3 was remarkably expressed in flower buds and the prickles of young fruits. Notably, overexpression of RrEGL3 produced significantly more trichomes compared with wild type. Besides, RrEGL3 was able to functionally complement the glabrous phenotype of gl3 egl3 and ttg1 mutants. Surprisingly, overexpression of RrGL3 did not influence trichome patterning in Arabidopsis. Finally, while RrEGL3 was found to interact with both TTG1 and GL1 in vitro and in vivo, in contrast, RrGL3 only interacted with GL1. The inability of RrGL3 to interact with TTG1 suggests functional divergence between RrGL3 and RrEGL3. These results illustrated that highly expressed RrEGL3 mediates trichome development in Arabidopsis by forming a GL1-RrEGL3-TTG1 complex, proposing RrEGL3 as a good candidate for controlling prickles in R. roxburghii. This study provides insights into the molecular mechanisms concerning the development of prickles in the Rosaceae family, and provides the theoretical basis for cultivation of prickle-free fruits. Key message: RrEGL3 expressed highly in tissues presenting prickles of Rosa roxburghii could mediated trichome development in Arabidopsis by forming GL1-RrEGL3-TTG1 complex. [ABSTRACT FROM AUTHOR]

Microwave plasma chemical vapor deposition (MPCVD) has received tremendous research interest in fabrication of carbon nanotubes (CNTs) due to its unique advantages of high reactivity, rapid heating, no pollution, good controllability, etc. It would be meaningful to summarize the efforts that have been devoted in this area. Up to now, no such review has been seen in the literature. In this review, a summarization and discussion of the MPCVD devices applied in CNTs fabrication are firstly given, followed by the discussion on effect and affecting mechanisms of H2 plasma pretreatment, nitrogen atoms in the reacting gases and microwave power. Notably, the parameters of as-synthesized CNTs products and the corresponding synthesizing MPCVD conditions are listed out. Finally, the capabilities of MPCVD in facilitating atmospheric-pressure, low-temperature and in situ growth of CNTs are reviewed. This review can give a comprehensive grasp of current progress and understanding of MPCVD in preparation of CNTs and may provide a useful guidance for readers to design their fabricating systems to obtained required CNTs using MPCVD. [ABSTRACT FROM AUTHOR]

Background: LBDs, as the plant-specific gene family, play essential roles in lateral organ development, plant regeneration, as well as abiotic stress and pathogen response. However, the number and characteristic of LBD genes in Pyscomitrella patens were still obscure. Objective: This study was performed to identify the LBD family gene in moss and to determine the expression profiles of LBDs under the abiotic and pathogen stress. Methods: Complete genome sequences and transcriptomes of P. patens were downloaded from the Ensembl plant database. The hidden Markov model-based profile of the conserved LOB domain was submitted as a query to identify all potential LOB domain sequences with HMMER software. Expression profiles of PpLBDs were obtained based on the GEO public database and qRT-PCR analysis. Results: In this study, a total of 31 LBDs were identified in the P. patens genome, divided into two classes based on the presence of the leucine zipper-like coiled-coil motif. A phylogenetic relationship was obtained between 31 proteins from P. patens and 43 proteins from the Arabidopsis thaliana genome, providing insights into their conserved and potential functions. Furthermore, the exon–intron organization of each PpLBD were analyzed. All PpLBD contain the conserved DNA binding motif (CX2CX6CX3C zinc finger-like motif), and were predicted to be located in cell nuclear. The 31 PpLBD genes were unevenly assigned to 18 out of 27 chromosomes based on the physical positions. Among these genes, PpLBD27 was not only remarkably highest expressed in desiccation, but also a susceptible gene to pathogens through jasmonic acid-mediated signaling pathway. Most of PpLBDs were up-regulated with the treatment of mannitol. These results showed they were differentially induced and their potential functions in the environmental stimulus of the early terrestrial colonizers. Conclusion: Despite significant differences in the life cycle in P. patens and flowering plants, their functions involved in abiotic and biotic stress-regulated by LBDs have been identified and appear to be conserved in the two lineages. These results provided a comprehensive analysis of PpLBDs and paved insights into studies aimed at a better understanding of PpLBDs. [ABSTRACT FROM AUTHOR]

During 2009, an outbreak of hand, foot, and mouth disease (HFMD) enrolled 490 people in Henan Province, causing the death of two children. In order to investigate the pathogens responsible for this outbreak and characterize their genetic characteristics, a total of 508 clinical specimens (stool, throat swab, and vesicle fluid) were collected from the Center for Disease Control and Prevention of Henan Province. Virological investigations (virus isolation, conventional reverse transcription PCR, and real-time reverse transcription PCR) and phylogenetic analysis were performed. It was found that human enterovirus 71 (EV71) was the main pathogen causing this outbreak, while Coxsackievirus A16 (CoxA16) played only a subsidiary role. Phylogenetic analysis of 24 EV71 isolates collected during the period from March 11 to July 24, 2009 showed that they belonged to subgenotypes C4 and C5. Our study for the first time characterizes the epidemiology of HFMD and EV71 infection in Henan Province in 2009 and provides the first direct evidence of the genotype of EV71 circulating in Henan Province at that time. Our study should facilitate the development of public health measures for the control and prevention of HFMD and EV71 infection in at-risk individuals in China. [ABSTRACT FROM AUTHOR]

The single-component type-II NADH dehydrogenases (NDH-2s) serve as alternatives to the multisubunit respiratory complex?I (type-I NADH dehydrogenase (NDH-1), also called NADH:ubiquinone oxidoreductase; EC 1.6.5.3) in catalysing electron transfer from NADH to ubiquinone in the mitochondrial respiratory chain. The yeast NDH-2 (Ndi1) oxidizes NADH on the matrix side and reduces ubiquinone to maintain mitochondrial NADH/NAD+ homeostasis. Ndi1 is a potential therapeutic agent for human diseases caused by complex?I defects, particularly Parkinson's disease, because its expression restores the mitochondrial activity in animals with complex?I deficiency. NDH-2s in pathogenic microorganisms are viable targets for new antibiotics. Here we solve the crystal structures of Ndi1 in its substrate-free, NADH-, ubiquinone- and NADH-ubiquinone-bound states, to help understand the catalytic mechanism of NDH-2s. We find that Ndi1 homodimerization through its carboxy-terminal domain is critical for its catalytic activity and membrane targeting. The structures reveal two ubiquinone-binding sites (UQI and UQII) in Ndi1. NADH and UQI can bind to Ndi1 simultaneously to form a substrate-protein complex. We propose that UQI interacts with FAD to act as an intermediate for electron transfer, and that NADH transfers electrons through this FAD-UQI complex to UQII. Together our data reveal the regulatory and catalytic mechanisms of Ndi1 and may facilitate the development or targeting of NDH-2s for potential therapeutic applications. [ABSTRACT FROM AUTHOR]

Alternate layers of Al2O3 and ZrO2 nanocomposite films were prepared on silicon wafers and glass substrates at room temperature using the electrostatic self-assembly monolayer (ESAM) process. The versatile approach of the ESAM process provides the possibility of integrating diverse inorganic colloids on the nanosize level in a layer-by-layer or block-by-block fashion. Further, it allows the combination of inorganic colloids and organic molecules, making it possible to fabricate thick films with large pores and good stress relaxation. Highly ordered, micron-thick films have been formed, sintered, and characterized by scanning electron microscopy and ellipsometry. There is no significant visible crack formation for Al2O3–ZrO2 composite films after heat treatment at 1200°C for 2 h, although significant thickness reduction occurs. The hardness and Young's modulus of these films before and after sintering were measured using nanoindentation techniques. [ABSTRACT FROM AUTHOR]