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:We optimized the key parameters of m6A MeRIP-seq, including the starting amount of RNA, RNA fragmentation, antibody selection, MeRIP washing/elution conditions, methods for RNA library construction and the bioinformatics analysis pipeline. With the optimized immunoprecipitation conditions and a post-amplification rRNA depletion strategy, we were able to profile the m6A epitranscriptome using 2 µg of total RNA. We identified ~12,000 m6A peaks with a high signal/noise ratio from two lung adenocarcinoma (ADC) patient tumors. Through integrative analysis of the transcriptome, m6A epitranscriptome and proteome data in the same patient tumors, we identified dynamics at the m6A level that accounts for the discordance between mRNA and protein levels in these tumors.
Project description:Mouse C2C12 myoblasts were used to mimic skeletal muscle differentiation in vitro.Using RNA-seq and MeRIP-seq, we generated the tascriptome and epitranscriptome data of undifferentited C2C12 myoblasts in growth medium (GM) and differentiated myotubes in differentitation medium for 4 days (D4).
Project description:The intestinal microbiota modulates host physiology and gene expression via mechanisms that are not fully understood. A recently discovered layer of gene expression regulation is N6-methyladenosine (m6A) and N6,2′ -O-dimethyladenosine (m6Am) modifications of mRNA. To unveil if these epitranscriptomic marks are affected by the gut microbiota, we performed methylated RNA-immunoprecipitation and sequencing (MeRIP-seq) to examine m6A-modifications in transcripts of mice displaying either a conventional, or a modified, or no gut microbiota and discovered that the microbiota has a strong influence on m6A- modifications in the cecum, and also, albeit to a lesser extent, in the liver, affecting pathways related to metabolism, inflammatory and antimicrobial responses . We furthermore analysed expression levels of several known writer and eraser enzymes and found the methyltransferase Mettl16 to be downregulated in absence of a microbiota. As a consequence, one of its targets, the S-adenosyl methionine synthase Mat2a was less expressed in mice without gut flora. We furthermore show that distinct commensal bacteria, Akkermansia muciniphila, Lactobacillus plantarum can affect specific m6A modifications. Together, we report here epitranscriptomic modifications as an additional level of interaction in the complex interplay between commensal bacteria and their host.
Project description:We performed m6A-RIPs in Ascl1-induced neurons (iNeurons) to investigate the neuronal m6A epitranscriptome. Immunoprecipitation was done twice using two different antibodies, acquired from Abcam and Synaptic Systems (SySy), allowing for a more robust detection of m6A modification marks. Additionally, RIP-seq was performed separately with intact and fragmented RNA. The former approach allowed to identify proportions of m6A-modified transcripts among the total number, while the latter approach provided the information to identify genomic coordinates of m6A peaks.
Project description:We report an epitranscriptome-wide mapping of m6A-modified circRNAs (m6A-circRNA) in oral squamous cell carcinoma (OSCC). Utilizing the data of m6A-circRNAs epitranscriptomic microarray analysis, we found that m6A-circRNAs exhibited their particular modification style in OSCC. anti-m6A antibody Synaptic Systems, cat. No. 202003)
Project description:The mRNA m6A reader YTHDF2 is overexpressed in a broad spectrum of human acute myeloid leukemias (AML). To understand the role of YTHDF2 in AML, we generated m6A meRIP-seq libraries form Ythdf2fl/fl (Ythdf2CTL) pre-leukemic cells.
Project description:The mRNA m6A reader YTHDF2 is overexpressed in a broad spectrum of human acute myeloid leukemias (AML). To understand the role of YTHDF2 in AML, we generated m6A meRIP-seq libraries form Ythdf2fl/fl; Vav-iCre (Ythdf2CKO) pre-leukemic cells.
Project description:N6-methyl adenosine (m6A) is one of the most important RNA modifications involved in several biological and pathological processes, including cancer. Dysregulation of m6A has been linked with tumor initiation, progression, and metastasis of several cancer types, including colon cancer. A transcriptome of colon cancer describes the dysregulated coding and non-coding RNAs but does not reveal the mechanisms like m6A modifications that determine the post-transcriptional and pre-translational regulations. Epi-transcriptome profiling of m6A in colon cancer cell lines was performed using Methylated RNA Immunoprecipitation (MeRIP) sequencing. Overall, the study illustrates the distribution of m6A across the transcriptome of various colon cancer cell lines.