Project description:N6-methyladenosine (m6A) is the most prominent mRNA modification in eukaryotes, and its potential regulatory role has recently been identified in mammals, plants, and yeast. However, how m6A methylation regulates spermatogenesis remains unknown. In this study, cattle-yak testis tissue was used as the experimental material, and the m6A map was generated through preliminary experiments and methylated RNA immunoprecipitation sequencing. Only spermatogonia and Sertoli cells were observed in cattle-yak testis tissue. Experiments examining the expression of methylation-related enzymes and the overall methylation level showed that the methylation level in the testis of the cattle-yak was slightly lower than that of the sexually mature yak, but significantly higher than that of the pre-sexually mature yak. Annotation analysis indicated that differentially methylated peaks were most frequently concentrated in exonic regions, followed by 3'UTR and finally 5'UTR regions. Through enrichment analysis of differentially expressed genes and differentially methylated corresponding genes, GO analysis of T-vs-Y group mainly involved spermatogenesis, including cytoskeleton, actin binding, etc. KEGG analysis showed that the differential genes were mainly enriched in actin cytoskeleton regulation and MAPK signaling pathway. GO analysis of the T-vs-M group mainly involved protein ubiquitination, ubiquitin ligase complexes, ubiquitin-dependent protein catabolism and endocytosis. KEGG analysis mainly involved apoptosis and Fanconi anemia pathways. This study will lay the foundation for elucidating the molecular mechanism of m6A in male sterility of cattle-yak.
Project description:<p>Despite the nuclear localization of the m6A machinery, the genomes of multiple exclusively-cytoplasmic RNA viruses, such as chikungunya (CHIKV) and dengue (DENV), are reported to be extensively m6A-modified. However, these findings are mostly based on m6A-seq, an antibody-dependent technique with a high rate of false positives. Here, we addressed the presence of m6A in CHIKV and DENV RNAs. For this, we combined m6A-seq and the antibody-independent SELECT and nanopore direct RNA sequencing techniques with functional, molecular, and mutagenesis studies. Following this comprehensive analysis, we found no evidence of m6A modification in CHIKV or DENV transcripts. Furthermore, depletion of key components of the host m6A machinery did not affect CHIKV or DENV infection. Moreover, CHIKV or DENV infection had no effect on the m6A machinery’s localization. Our results challenge the prevailing notion that m6A modification is a general feature of cytoplasmic RNA viruses and underscore the importance of validating RNA modifications with orthogonal approaches.</p>
Project description:m6A profiling in two accessions of Arabidopsis thaliana (Can-0 and Hen-16) using the m6A-targeted antibody coupled with high-throughput sequencing m6A-seq in two accessions of Arabidopsis, two replicates for each sample
Project description:In this study, we investigated the transcriptomic response of Streptococcus pneumoniae D39 to sialic acid (N-acetylneuraminic acid: Neu5Ac). Transcriptome comparison of the D39 wild-type grown in M17 medium with and without sialic acid revealed the elevated expression of various genes and operons including the nan gene cluster (nan operon-I and nanA gene). Our microarray analysis and promoter-lacZ fusion studies showed that the transcriptional regulator NanR acts as a transcriptional activator of nan operon-I and the nanA gene in the presence of sialic acid. The putative regulatory site of NanR in the promoter region of nan operon-I is predicted and confirmed by promoter truncation experiments. Furthermore, the role of CcpA in the regulation of the nan gene cluster is demonstrated through microarray analysis and promoter-lacZ fusion studies, suggesting that in the presence of sialic acid and glucose, CcpA represses the expression of nan operon-I while the expression of the nanA gene is CcpA-independent. This SuperSeries is composed of the SubSeries listed below.
Project description:m6A is a ubiquitous RNA modification in eukaryotes. Transcriptome-wide m6A patterns in Arabidopsis have been assayed recently. However, m6A differential patterns among organs have not been well characterized. The goal of the study is to comprehensively analyze m6A patterns of numerous types of RNAs, the relationship between transcript level and m6A methylation extent, and m6A differential patterns among organs in Arabidopsis. In total, 18 libraries were sequneced. For the 3 organs: leaf, flower and root, each organ has mRNA-Seq, m6A-Seq and Input sequenced. And each sequence has 2 replicats.