Cyberlindnera fabianii is a Baijiu-associated non-Saccharomyces yeast that may encounter transient heat stress during fermentation, but the mechanisms underlying its thermotolerance remain poorly understood. Here, we evaluated heat survival, culture turbidity, culturability, JC-1-based relative mitochondrial polarization, and transcriptomic responses of C. fabianii at 45 °C under different glucose concentrations. C. fabianii showed higher CFU-based survival than Saccharomyces cerevisiae after 2 h of heat exposure. During prolonged incubation, 30% glucose improved culturability and was accompanied by higher relative mitochondrial membrane potential (MMP), less disrupted JC-1 staining patterns, weaker repression of glycolysis- and TCA-cycle-related transcripts, and increased PPP-related transcript levels together with upregulation of ROS-scavenging genes. These findings indicate a glucose-associated improvement in heat-stress tolerance, particularly involving early maintenance of mitochondrial polarization and metabolic/redox-related transcriptional responses; however, the current data do not determine whether this effect is transient or long-lasting. Under glucose-limited conditions, glycerol or xylose co-feeding increased turbidity and partially supported CFU retention, with substrate-dependent differences in extracellular glucose consumption. Overall, these findings suggest that glucose availability is closely associated with thermotolerance and mitochondrial polarization in C. fabianii, and that, in liquid culture, selected co-substrates may partially reproduce aspects of the high-glucose-associated phenotype without requiring comparable glucose supplementation.

Porcine skeletal muscle satellite cells (PSCs) are the core stem cell population for the development of porcine skeletal muscle. In postnatal piglets, PSCs can differentiate into myoblasts and fuse with existing muscle fibers, increasing muscle fiber volume. While the long noncoding RNA MEG3 (MEG3) has been shown to modulate PSC development, its mechanisms remain nebulous. Here, we aim to explore the mechanism whereby MEG3 modulates PSC development. Core interaction regions between MEG3 and CDC23 were detected using truncated constructs combined with RNA pull-down and RNA immunoprecipitation (RIP). Potential CDC23 target proteins were analyzed using coimmunoprecipitation (Co-IP) and bimolecular fluorescence complementation (BiFC). The potential mechanism of MEG3 modulation was then further explored by employing MG-132 and cycloheximide (CHX) treatment and ubiquitination assays. Finally, downstream signaling pathways associated with MEG3 were detected by transcriptome sequencing (RNA-seq) and western blot analysis. The 787–839 nt region of MEG3 and the 464–594aa region of CDC23 are necessary for binding, with MEG3 (Δ787–839 nt) showing a reduced inhibitory effect on proliferation and promoting effect on differentiation. Furthermore, CDC23 promotes HMGA1 ubiquitination via a K48 linkage at the K7 site, significantly shortening its half-life. MEG3 competitively binds CDC23, enhancing HMGA1 stability and protecting it from proteasome degradation. Functional detection and transcriptome sequencing further clarified that MEG3 acts through HMGA1-mediate inhibition of proliferation and promotion of differentiation. Furthermore, MEG3 knockdown, and subsequent HMGA1 downregulation, mediates the activation of ERK signaling, thereby promoting PSC proliferation and inhibiting differentiation. This study demonstrates a novel mechanism of MEG3 regulation in PSC development, implicates potential genetic targets, and provides a theoretical basis for accelerated porcine skeletal muscle development.

Skeletal muscle satellite cell proliferation and differentiation are important stages in skeletal muscle development, and long non-coding RNAs (lncRNAs) play important roles in both stages. We previously determined the basal functions of lncRNA H19 (H19) and the drebrin 1 (DBN1) gene in porcine skeletal muscle satellite cells (PSCs). However, the mechanisms for H19 and DBN1 regulation of the proliferation and differentiation of PSCs are still unclear. In this study, double luciferase report and pull down results confirmed H19 upregulates DBN1 expression by acting as a miR-935/miR-296-5p decoy. The western blotting results showed upregulated DBN expression activates the p38 mitogen-activated protein kinase (MAPK) pathway to inhibit PSC proliferation and promote differentiation. Moreover, ChIP results showed H19 transcription is regulated by the upstream transcription factor myc-associated zinc finger protein (MAZ). In conclusion, we resolved the mechanism for H19 regulation of proliferation and differentiation of PSCs, contributing to a deeper understanding of the epigenetic regulation of skeletal muscle development and will accelerate advancements in animal genetic improvement.

Zygosaccharomyces rouxii is a typical aroma-producing yeast in food brewing, but it has low heat resistance and poor proliferation ability at high temperature. Trehalose is generally considered to be a protective agent that helps stable yeast cells resist heat shock stress, but its functional mechanism for yeast cells in the adaptation period under heat stress is unclear. In this study, the physiological metabolism changes, specific gene transcription expression characteristics, and transcriptome differences of Z. rouxii under different carbon sources under high-temperature stress (40 °C) were compared to explore the mechanism of trehalose inducing Z. rouxii to recover and proliferate under high-temperature stress during the adaptation period. The results showed that high concentration of trehalose (20% Tre) could not be used as the main carbon source for the proliferation of Z. rouxii under long-term high-temperature stress, but it helped to maintain the stability of the cell population. The intracellular trehalose of Z. rouxii was mainly derived from the synthesis and metabolism of intracellular glucose, and the extracellular acetic acid concentration showed an upward trend with the improvement of yeast growth. A high concentration of trehalose (20% Tre) can promote the expression of high glucose receptor gene GRT2 (12.0-fold) and induce the up-regulation of HSF1 (27.1-fold), MSN4 (58.9-fold), HXK1 (8.3-fold), and other signal transduction protein genes, and the increase of trehalose concentration will maintain the temporal up-regulation of these genes. Transcriptome analysis showed that trehalose concentration and the presence of glucose had a significant effect on the gene expression of Z. rouxii under high-temperature stress. In summary, trehalose assists Z. rouxii in adapting to high temperature by changing gene expression levels, and assists Z. rouxii in absorbing glucose to achieve cell proliferation.

Cell division cycle 23 (CDC23) is a component of the tetratricopeptide repeat (TPR) subunit in the anaphase-promoting complex or cyclosome (APC/C) complex, which participates in the regulation of mitosis in eukaryotes. However, the regulatory model and mechanism by which the CDC23 gene regulates muscle production in pigs are largely unknown. In this study, we investigated the expression of CDC23 in pigs, and the results indicated that CDC23 is widely expressed in various tissues and organs. In vitro cell experiments have demonstrated that CDC23 promotes the proliferation of myoblasts, as well as significantly positively regulating the differentiation of skeletal muscle satellite cells. In addition, Gene Set Enrichment Analysis (GSEA) revealed a significant downregulation of the cell cycle pathway during the differentiation process of skeletal muscle satellite cells. The protein–protein interaction (PPI) network showed a high degree of interaction between genes related to the cell cycle pathway and CDC23. Subsequently, in differentiated myocytes induced after overexpression of CDC23, the level of CDC23 exhibited a significant negative correlation with the expression of key factors in the cell cycle pathway, suggesting that CDC23 may be involved in the inhibition of the cell cycle signaling pathway in order to promote the differentiation process. In summary, we preliminarily determined the function of CDC23 with the aim of providing new insights into molecular regulation during porcine skeletal muscle development.

Structural variants (SVs), such as deletions (DELs) and insertions (INSs), contribute substantially to pig genetic diversity and phenotypic variation. Using a library of SVs discovered from long-read primary assemblies and short-read sequenced genomes, we map pig genomic SVs with a graph-based method for re-genotyping SVs in 402 genomes. Our results demonstrate that those SVs harboring specific trait-associated genes may greatly shape pig domestication and local adaptation. Further characterization of SVs reveals that some population-stratified SVs may alter the transcription of genes by affecting regulatory elements. We identify that the genotypes of two DELs (296-bp DEL, chr7: 52,172,101-52,172,397; 278-bp DEL, chr18: 23,840,143-23,840,421) located in muscle-specific enhancers are associated with the expression of target genes related to meat quality (FSD2) and muscle fiber hypertrophy (LMOD2 and WASL) in pigs. Our results highlight the role of SVs in domestic porcine evolution, and the identified candidate functional genes and SVs are valuable resources for future genomic research and breeding programs in pigs.

Myogenic differentiation is a complex biological process that is regulated by multiple factors, among which long noncoding RNAs (lncRNAs) play an essential role. However, in-depth studies on the regulatory mechanisms of long noncoding RNAs (lncRNAs) in myogenic differentiation are limited. In this study, we characterized the role of the novel lncRNA TCONS_00323213, which is upregulated during porcine skeletal muscle satellite cell (PSC) differentiation in myogenesis. We found that TCONS_00323213 affected the proliferation and differentiation of PSC in vitro. We performed quantitative polymerase chain reaction (qPCR), 5-ethynyl-20-deoxyuridine (EdU), western blotting, immunofluorescence staining, pull-down assays, and cleavage under targets and tagmentation (CUT and Tag) assays to clarify the effects and action mechanisms of TCONS_00323213. LncRNA TCONS_00323213 inhibited myoblast proliferation based on analyses of cell survival rates during PSC proliferation. Functional analyses revealed that TCONS_00323213 promotes cell differentiation and enhances myogenin (MyoG), myosin heavy chain (MyHC), and myocyte enhancer factor 2 (MEF2C) during myoblast differentiation. As determined by pull-down and RNA immunoprecipitation (RIP) assays, the lncRNA TCONS_00323213 interacted with PBX/Knotted Homeobox 2 (PKNOX2). CUT and Tag assays showed that PKNOX2 was significantly enriched on the MyoG promoter after lncRNA TCONS_00323213 knockdown. Our findings demonstrate that the interaction between lncRNA TCONS_00323213 and PKNOX2 relieves the inhibitory effect of PKNOX2 on the MyoG promoter, increases its expression, and promotes PSC differentiation. This novel role of lncRNA TCONS_00323213 sheds light on the molecular mechanisms by which lncRNAs regulate porcine myogenesis.

细菌可以通过多种方式产生对抗菌药物的耐药性,其中最为常见的方式之一为获得携带有耐药基因的质粒.耐药质粒可以在菌株之间转移,导致耐药性的广泛传播,因此消除耐药质粒是缓解细菌耐药扩散的关键.本综述介绍了基于物理、化学以及生物学的细菌耐药质粒消除方法的研究进展,并阐述了质粒消除的机理,为今后探寻安全有效地消除耐药质粒的研究方法提供参考.

Long non-coding RNAs (lncRNAs) are involved in the process of muscle cell differentiation and play an important role. Previous studies have shown that lncRNA-MEG3 promotes the differentiation of porcine skeletal muscle satellite cells (PSCs), but the regulatory mechanism of MEG3 interaction with target protein has not been well studied. We demonstrated that MEG3 can bind dihydrolipoamide succinyltransferase (DLST) by RNA pull down and RIP-qPCR. Subsequently, knockdown and overexpression experiments showed that DLST promotes PSCs differentiation. Rescue experiments showed that the expression of DLST protein was significantly increased with MEG3 overexpression and decreased with MEG3 knockdown, while its mRNA expression was not changed. Furthermore, we have successfully predicted and validated that the transcription factor myogenic differentiation (MYOD) binds to the MEG3 core promoter though utilizing chromatin immunoprecipitation (CHIP) and luciferase reporter assays. The results indicated that MYOD acts as a transcription factor of MEG3 to promote MEG3 transcription. Knockdown of MEG3 in vivo indicated that MEG3 is involved in skeletal muscle regeneration. It is concluded that MYOD acts as a transcription factor to induce MEG3 expression. MEG3 acts as a molecular scaffold to bind and promote DLST protein expression. This paper provides a new molecular mechanism for MEG3 to promote the differentiation of PSCs.

测量溶液折射率具有重要的理论和实际意义.文章基于迈克尔逊干涉仪和智能手机研究透明液体折射率测量装置和方法,并应用于食盐和蔗糖溶液折射率的定量测量.实验结果表明,在最佳工作角度时,该测量装置和方法能够定量测量透明液体折射率,测量装置性能稳定,测量方法精度较高,食盐和蔗糖溶液折射率测量百分偏差分辨为3％和2％左右.采用智能手机光学传感器及免费应用程序—Phyphox,代替人眼读取激光干涉条纹变化情况,不仅解决了传统迈克尔逊干涉实验人眼读数的痛点,还提高了实验客观性和准确性.实验研究有助于拓展迈克尔逊干涉仪和智能手机在物理教学和研究中的应用领域,加深学生对波动光学和双光束干涉的理解和认识.

在开放式教学改革的基础上,对大学物理实验教学内容和模式进一步深化革新.在教学模式上,构建虚实结合的BOPPPS教学模式,实现自主化、泛在化的实验课程学习过程;在教学内容上,重构"有趣、有度、有用、有味"的模块化实验教学内容体系,建立了"多元化+信息化+过程化"的教学评价体系.实践表明:虚实结合的大学物理实验BOPPPS教学模式更好地调动了学生学习的主动性与创造性,实现了价值塑造、能力培养、知识传授的育人目标,体现了农业院校大学物理实验的特色.

Multidrug resistance (MDR) in Enterobacteriaceae including resistance to quinolones is rising worldwide. The plasmid-mediated quinolone resistance (PMQR) gene qnrS is prevalent in Enterobacteriaceae. However, the qnrS gene is rarely found in Enterobacter hormaechei (E. hormaechei). Here, we reported one multidrug resistant E. hormaechei strain M1 carrying the qnrS1 and blaTEM-1 genes. This study was to analyze the characteristics of MDR E. hormaechei strain M1. The E. hormaechei strain M1 was identified as Enterobacter cloacae complex by biochemical assay and 16S rRNA sequencing. The whole genome was sequenced by the Oxford Nanopore method. Taxonomy of the E. hormaechei was based on multilocus sequence typing (MLST). The qnrS with the other antibiotic resistance genes were coexisted on IncF plasmid (pM1). Besides, the virulence factors associated with pathogenicity were also located on pM1. The qnrS1 gene was located between insertion element IS2A (upstream) and transposition element ISKra4 (downstream). The comparison result of IncF plasmids revealed that they had a common plasmid backbone. Susceptibility experiment revealed that the E. hormaechei M1 showed extensive resistance to the clinical antimicrobials. The conjugation transfer was performed by filter membrane incubation method. The competition and plasmid stability assays suggested the host bacteria carrying qnrS had an energy burden. As far as we know, this is the first report that E. hormaechei carrying qnrS was isolated from chicken feed. The chicken feed and poultry products could serve as a vehicle for these MDR bacteria, which could transfer between animals and humans through the food chain. We need to pay close attention to the epidemiology of E. hormaechei and prevent their further dissemination. IMPORTANCE Enterobacter hormaechei is an opportunistic pathogen. It can cause infections in humans and animals. Plasmid-mediated quinolone resistance (PMQR) gene qnrS can be transferred intergenus, which is leading to increase the quinolone resistance levels in Enterobacteriaceae. Chicken feed could serve as a vehicle for the MDR E. hormaechei. Therefore, antibiotic-resistance genes (ARGs) might be transferred to the intestinal flora after entering the gastrointestinal tract with the feed. Furthermore, antibiotic-resistant bacteria (ARB) were also excreted into environment with feces, posing a huge threat to public health. This requires us to monitor the ARB and antibiotic-resistant plasmids in the feed. Here, we demonstrated the characteristics of one MDR E. hormaechei isolate from chicken feed. The plasmid carrying the qnrS gene is a conjugative plasmid with transferability. The presence of plasmid carrying antibiotic-resistance genes requires the maintenance of antibiotic pressure. In addition, the E. hormaechei M1 belonged to new sequence type (ST). These data show the MDR E. hormaechei M1 is a novel strain that requires our further research.

This study aimed to determine the effect of enrofloxacin (ENR) on the transfer of the plasmid-mediated quinolone resistance (PMQR) gene qnrS from opportunistic pathogen Escherichia coli (E2) to Salmonella Enteritidis (SE211) and to analyze the resistance characteristics of SE211-qnrS isolates. The plasmid carrying qnrS gene of E2 was sequenced by Oxford Nanopore technology. The plasmid carrying qnrS gene belonged to incompatibility group IncY. In vitro, the transfer experiment of IncY plasmid was performed by the liquid medium conjugation method. The conjugation transfer frequency of the IncY plasmid was 0.008 ± 0.0006 in the absence of ENR, 0.012 ± 0.003 in 1/32 MICENR, 0.01 ± 0.008 in 1/8 MICENR, and 0.03 ± 0.015 (Mean±SD) in 1/2 MICENR, respectively. After inoculation of E. coli E2 and SE211, chickens were treated with different doses of ENR (3.03, 10, and 50 mg/kg b.w.) for 7 days consecutively. To screen the SE211-qnrS strains from intestinal tract of chickens, the resistance genes and susceptibility of isolates were identified. The amount of E. coli E2 and the copy number of qnrS gene in the chicken intestinal tract were determined by colony counting and qPCR, respectively. In vivo, more SE211-qnrS strains were isolated from the treated group compared with the untreated group. SE211-qnrS strains not only obtained IncY plasmid, but also showed similar resistance phenotype as E2. In conclusion, ENR treatment can promote the spread of a IncY-resistance plasmid carrying the qnrS fluoroquinolone-resistance gene in Escherichia coli and the development of drug-resistant bacteria.

运用磁学理论和仿真软件,从漆包线和通水导线两种方案,分析讨论了在体积较大磁感应强度较高的磁场设计需求下,螺线管的尺寸、重量和散热问题.为工程实践提供参考,设计理念、思路和方案也将为相关设备的设计制造提供借鉴.

Skeletal muscle growth plays a critical role during porcine muscle development stages. Genome-wide transcriptome analysis reveals that long intergenic non-coding RNAs (lincRNAs) are implicated as crucial regulator involving in epigenetic regulation. However, comprehensive analysis of lincRNAs in embryonic muscle development stages remain still elusive. Here, we investigated the transcriptome profiles of Duroc embryonic muscle tissues from days 33, 65, and 90 of gestation using RNA-seq, and 228 putative lincRNAs were identified. Moreover, these lincRNAs exhibit the characteristics of shorter transcripts length, longer exons, less exon numbers and lower expression level compared with protein-coding transcripts. Expression profile analysis showed that a total of 120 lincRNAs and 2638 mRNAs were differentially expressed. In addition, we also performed quantitative trait locus (QTL) mapping analysis for differentially expressed lincRNAs (DE lincRNAs), 113 of 120 DE lincRNAs were localized on 2200 QTLs, we observed many QTLs involved in growth and meat quality traits. Furthermore, we predicted potential target genes of DE lincRNAs in cis or trans regulation. Gene ontology and pathway analysis reveals that potential targets of DE lincRNAs mostly were enriched in the processes and pathways related to tissue development, MAPK signaling pathway, Wnt signaling pathway, TGF-beta signaling pathway and insulin signaling pathway, which involved in skeletal muscle physiological functions. Based on cluster analysis, co-expression network analysis of DE lincRNAs and their potential target genes indicated that DE lincRNAs highly regulated protein-coding genes associated with skeletal muscle development. In this study, many of the DE lincRNAs may play essential roles in pig muscle growth and muscle mass. Our study provides crucial information for further exploring the molecular mechanisms of lincRNAs during skeletal muscle development.

Neurons can detect weak target signals from complex background signals through stochastic resonance (SR) and vibrational resonance (VR) mechanisms. However, random phase variation of rapidly fluctuating background signals is generally ignored in classical VR or SR studies. Here, the rapidly fluctuating background signals are modeled by bounded noise with random rapidly fluctuating phase derived from Wiener process. Then, the influences of bounded noise on the weak signal detection are discussed in the FitzHugh–Nagumo (FHN) neuron. Numerical results reveal the occurrence of bounded noise-induced single- and biresonance as well as a transition between them. Randomness in phase can enhance the adaptability of neurons, but at the cost of signal detection performance so that neurons can work in more complex environments with a wider frequency range. More interestingly, bounded noise with appropriate parameters can not only optimize information transmission but also simultaneously reduce energy consumption. Finally, the potential mechanism of bounded noise is explained.

Robustness is a fundamental characteristic of biological systems since all living systems need to adapt to internal or external perturbations, unpredictable environments, stochastic events and unreliable components, and so on. A long-term challenge in systems biology is to reveal the origin of robustness underlying molecular regulator network. In this study, a simple Boolean model is used to investigate the global dynamic properties and robustness of cardiac progenitor cell (CPC) induced pluripotent stem cell network that governs reprogramming and directed differentiation process. It is demonstrated that two major attractors correspond to source and target cell phenotypes, respectively, and two dominating attracting trajectories characterise the biological pathways between two major cell phenotypes. In particular, the experimentally observed transition between different cell phenotypes can be reproduced and explained theoretically. Furthermore, the robustness of major attractors and trajectories is largely maintained with respect to small perturbations to the network. Taken together, the CPC-induced pluripotent stem cell network is extremely robustly designed for their functions.

As one of the most successful knowledge-based energy functions, the distance-dependent atom-pair potential is widely used in all aspects of protein structure prediction, including conformational search, model refinement, and model assessment. During the last two decades, great efforts have been made to improve the reference state of the potential, while other factors that also strongly affect the performance of the potential have been relatively less investigated.

Coherent feed-forward loops exist extensively in realistic biological regulatory systems, and are common signaling motifs. Here, we study the characteristics and the propagation mechanism of the output noise in a coherent feed-forward transcriptional regulatory loop that can be divided into a main road and branch. Using the linear noise approximation, we derive analytical formulae for the total noise of the full loop, the noise of the branch, and the noise of the main road, which are verified by the Gillespie algorithm. Importantly, we find that (i) compared with the branch motif or the main road motif, the full motif can effectively attenuate the output noise level; (ii) there is a transition point of system state such that the noise of the main road is dominated when the underlying system is below this point, whereas the noise of the branch is dominated when the system is beyond the point. The entire analysis reveals the mechanism of how the noise is generated and propagated in a simple yet representative signaling module.

MicroRNAs are a predominant type of small non-coding RNAs approximately 21 nucleotides in length that play an essential role at the post-transcriptional level by either RNA degradation, translational repression or both through an RNA-induced silencing complex. Identification of these molecules can aid the dissecting of their regulatory functions. The secondary structures of plant pre-miRNAs are much more complex than those of animal pre-miRNAs. In contrast to prediction tools for animal pre-miRNAs, much less effort has been contributed to plant pre-miRNAs. In this study, a set of novel knowledgebased energy features that has very high discriminatory power is proposed and incorporated with the existing features for specifically distinguishing the hairpins of real/pseudo plant pre-miRNAs. A promising performance area under a receiver operating characteristic curve of 0.9444 indicates that 5 knowledgebased energy features have very high discriminatory power. The 10-fold cross-validation result demonstrates that plantMirP with full features has a promising sensitivity of 92.61% and a specificity of 98.88%. Based on various different datasets, it was found that plantMirP has a higher prediction performance by comparison with miPlantPreMat, PlantMiRNAPred, triplet-SVM, and microPred. Meanwhile, plantMirP can greatly balance sensitivity and specificity for real/pseudo plant pre-miRNAs. Taken together, we developed a promising SVM-based program, plantMirP, for predicting plant pre-miRNAs by incorporating knowledgebased energy features. This study shows it to be a valuable tool for miRNA-related studies.