mRNA Imprinting: Co transcriptional association of proteins with mRNA

mRNA imprinting is the process in which proteins associate with the nascent transcript during transcription. Rpb4/7 are two RNA pol II subunits that were previously reported to be associated with the mRNA during transcription. It was found that this association continues throughout the mRNA lifecycle and regulates other stages that the mRNA is involved in. In the case of Rpb4/7, this imprinting affects transcription, translation, and degradation of certain transcripts, thus demonstrating that mRNA imprinting is a novel regulation mechanism.

In this current work we aimed to examine whether other versions of mRNA imprinting exist. For that purpose, we utilized a high-throughput, unbiased approach we term PROFIT (“PRofiling OF Imprinted Transcripts”) to identify co-transcriptionally bound proteins in a direct manner. In order to examine whether these proteins are indeed involved in transcription and post-transcriptional processes, we used BioID (Proximity-dependent-biotin-identification) system. The covalent addition of biotin allowed us to follow these proteins after they moved away from the pol II’s surroundings.

This research constitutes another step on the journey towards understanding “mRNA imprinting”, thus may also contribute to the study of regulation of gene expression.