PLX174852

GSE114311: Regulation of pre-mRNA splicing by m6A through the low-complexity protein hnRNPG and co-transcriptional pausing

• Organsim human
• Type RNASEQ
• Target gene
• Project ARCHS4

Co-transcriptional processing of nascent transcripts is coupled with transcription through the carboxy-terminal domain (CTD) of RNA polymerase II (RNAPII). The mRNA modification N6-methyladenosine (m6A) occurs co-transcriptionally and impacts pre-mRNA processing. How alternative splicing of pre-mRNA is co-transcriptionally regulated in an m6A-dependent manner is not well understood. Furthermore, splicing regulation through RNAPII pausing has been frequently suggested but the underlying control mechanism remains unclear. Here, we show that the m6A reader protein hnRNPG directly binds to the phosphorylated CTD of RNAPII using Arg-Gly-Gly (RGG) motifs in its low-complexity region. This RGG-phospho-CTD interaction and nascent RNA binding by hnRNPG enables its co-transcriptional association with RNAPII, resulting in transcriptome-wide regulation of alternative splicing and transcript abundance. m6A sites near exon splice sites in nascent mRNA further modulate hnRNPG binding and exon splicing. Exon inclusion is associated with RNAPII pausing downstream of the m6A site. Our results reveal an integrated nuclear mechanism of m6A-mediated gene regulation, in which an m6A reader protein regulates gene expression by using RGG motifs to co-transcriptionally interact with both RNAPII and m6A-modified nascent pre-mRNA, while the interplay between hnRNPG binding and RNAPII pausing modulates alternative splicing regulation. SOURCE: Tao Pan (taopan@uchicago.edu) - University of Chicago