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Biology subjects

yang, m.

Publications and source records attributed to yang, m..

4 recordsLinked to original sources

Small RNA ASpks2 Promote Mycobacterium tuberculosis Survival in Macrophages via Targeting Polyketide Synthase 2

Mycobacterium tuberculosis is the causative pathogen of human tuberculosis and a leading cause of death worldwide attributed to a single infectious agent. While small non-coding RNAs (sRNAs) have emerged as key regulators of bacterial pathogenicity, their specific roles and mechanisms in M. tuberculosis remain poorly understood. Here, we employed label-free quantitative proteomics, parallel reaction monitoring, and sRNA-seq analyses to identify proteomic differences between the virulent H37Rv and attenuated H37Ra strains. Bioinformatic analysis revealed significant enrichment of differentially expressed proteins involved in lipid metabolism and fatty acid biosynthesis, key pathways linked to M. tuberculosis virulence. We identified a novel sRNA, ASpks2, which was significantly downregulated in H37Rv. Functional validation demonstrated that ASpks2 directly targets the polyketide synthase 2 (pks2), modulating its expression to enhance M. tuberculosis survival in human macrophages THP-1 cells. By correlating the omics data with functional studies, this study identified a novel sRNA and its regulatory network in M. tuberculosis, which provides novel insight into the molecular pathogenesis of M. tuberculosis and may serve as a basis for the development of targeted therapies.

microbiology↗

Identification of a recombinant human astrovirus type 5 strain from an acute gastroenteritis outbreak in Beijing, China

Two samples positive for the same strain (2103CP) of human astrovirus (HAstV) were identified during an acute gastroenteritis outbreak in Beijing, China. A full genomic analysis showed that for both samples, open reading frame 1a (ORF1a) clustered with HAstV-1, whereas ORF1b and ORF2 clustered with HAstV-5. The recombination site was detected upstream of the region where ORF1a and ORF1b overlapped. Recombinant HAstV-5 strains were reported previously in China in 2013 and 2021. Our results indicate the need for continuous surveillance of the prevalence and evolution of this recombinant HAstV-5 in China.

evolutionary biology↗

Whole genome sequencing revealed genetic diversity and selection of Guangxi indigenous chickens

Guangxi chickens play an important role in promoting the high-quality development of the broiler industry in China, but their value and potential are yet to be discovered. To determine the genetic diversity and population structure of Guangxi indigenous chicken, we analyzed the whole genomes of 185 chicken from 8 phenotypically and geographically representative Guangxi chicken breeds, together with 12 RJFt, 12 BRA and 12 WL genomes available from previous studies. Calculation of heterozygosity (Hp), nucleotide diversity ({pi}), and LD level indicated that Guangxi populations were characterized by higher genetic diversity and lower differentiation than RJFt and commercial breeds except HGFC. Population structure analysis also confirmed the introgression from commercial broiler breeds. Each population clustered together while the overall differentiation was small, MA has the richest genetic diversity among all varieties. Selective sweep analysis revealed BCO2, EDN3 and other candidate genes have received strong selection in local breeds, these also provided novel breeding visual and data basis for future breeding.

genetics↗

SK4 calcium-activated potassium channels activated by sympathetic nerves enhances atrial fibrillation vulnerability in a canine model of acute stroke

New-onset atrial fibrillation (AF) is common in patients with acute stroke (AS). Studies have shown that intermediate-conductance KCa channels (SK4) play an important role in cardiomyocyte automaticity. The aim of this study was to investigate the effects of SK4 on AF vulnerability in dogs with AS. Eighteen dogs were randomly divided into a control group, AS group and left stellate ganglion ablation (LSGA) group. In the control group, dogs received craniotomy without right middle cerebral artery occlusion (MCAO). AS dogs were established using a cerebral ischemic model with right MCAO. LSGA dogs underwent MCAO, and LSGA was performed. Three days later, the dispersion of the effective refractory period (dERP) and AF vulnerability in the AS group were significantly increased compared with those in the control group and LSGA group. However, no significant difference in dERP and AF vulnerability was found between the control group and the LSGA group. The SK4 inhibitor (TRAM-34) completely inhibited the inducibility of AF in AS dogs. SK4 expression and levels of noradrenaline (NE), {beta}1-AR, p38 and c-Fos in the atrium were higher in the AS dogs than in the control group or LSGA group. However, no significant difference in SK4 expression or levels of NE, {beta}1-AR, p38 and c-Fos in the left atrium was observed between the control group and LSGA group. SK4 plays a key role in AF vulnerability in a canine model with AS. The effects of LSGA on AF vulnerability were associated with the p38 signaling pathways.

neuroscience↗