Project description:N6-methyladenosine (m6A) is a widespread reversible chemical modification of RNAs, implicated in many aspects of RNA metabolism. Little quantitative information exists as to either how many transcript copies of particular genes are m6A modified (âm6A levelsâ), or the relationship of m6A modification(s) to alternative RNA isoforms. To deconvolute the m6A epitranscriptome, we developed m6A level and isoform-characterization sequencing (m6A-LAIC-seq). We found that cells exhibit a broad range of non-stoichiometric m6A levels with cell type specificity. At the level of isoform characterization, we discovered widespread differences in use of tandem alternative polyadenylation (APA) sites by methylated and nonmethylated transcript isoforms of individual genes. Strikingly, there is a strong bias for methylated transcripts to be coupled with proximal APA sites, resulting in shortened 3â untranslated regions (3â-UTRs), while nonmethylated transcript isoforms tend to use distal APA sites. m6A-LAIC-seq yields a new perspective on transcriptome complexity and links APA usage to m6A modifications. m6A-LAIC-seq of H1-ESC and GM12878 cell lines, each cell line has two replicates
Project description:To investigate the effect of HSATIII lncRNA on m6A modification, we performed m6A-RIP(RNA immuno precipitation) RNA-seq from heat shock-exposed HeLa cells upon HSATIII knockdown.
Project description:The N6-methyladenosine (m6A) is the most abundant internal modification in almost all eukaryotic messenger RNAs, and is dynamically regulated. Therefore, identification of m6A readers is especially important in determining the cellular function of m6A. YTHDF2 has recently been characterized as the first m6A reader that regulates the cytoplasmic stability of methylated RNA. Here we show that YTHDC1 is a nuclear m6A reader and report the crystal structure of the YTH domain of YTHDC1 bound to m6A-containing RNA. We further determined the structure of another YTH domain, YTHDF1, and found that the YTH domain utilizes a conserved aromatic cage to specifically recognize the methyl group of m6A. Our structural characterizations of the YTHDC1-m6A RNA complex also shed light on the molecular basis for the preferential binding of the GG(m6A)C sequence by YTHDC1 and confirm the YTH domain as a specific m6A RNA reader. PAR-CLIP (Photoactivatable-Ribonucleoside-Enhanced Crosslinking and Immunoprecipitation) was applied to human YTHDC1 protein to identify its binding sites.
Project description:We report the application of MeRIP-seq to map m6A peaks in wild type and METTL5 KO HeLa cells to investigate targets of the m6A methyltransferase METTL5.
Project description:MeRIPSeq of HeLa cells synchronized by a double thymidine block to obtain the cell cycle phases and work with total RNA to study m6A mark in mRNA without polyA tail RNA seq of HeLa cells synchronized by a double thymidine block to obtain the cell cycle phases and work with total RNA to study mRNA without polyA tail
Project description:To investigate the m6A profiles of full-length L1 RNA, we use MeRIP-seq in HeLa cells expressing reporter L1. We find that L1 RNA contains functional m6A sites, predominantly in 5'UTR.
Project description:We have performed a epitranscriptomics study in which we first tretaed DMSO as a negative control and cisplatin in HeLa cells. Total RNA was isolated from control as well as CP treated cells and apoptotic rate was determined by flow cytometry. Total RNAs were subjected to miCLIP to identify differentially m6A methylated RNAs. We then transcriptionally analyzed apoptotic genes which have differential m6A methylation in CP tretament by qPCR. Afterthat, candidate genes were examined at the level of translation by polysome fractioantion assay.
