Repressor Of Rna Polymerase Iii Transcription Maf1 Homolog (MAF1) Reagents

Repressor of RNA polymerase III transcription MAF1 homolog

Plays a role in the repression of RNA polymerase III-mediated transcription in response to changing nutritional, environmental and cellular stress conditions to balance the production of highly abundant tRNAs, 5S rRNA, and other small non-coding RNAs with cell growth and maintenance. Plays also a key role in cell fate determination by promoting mesorderm induction and adipocyte differentiation. Mechanistically, associates with the RNA polymerase III clamp and thereby impairs its recruitment to the complex made of the promoter DNA, TBP and the initiation factor TFIIIB. When nutrients are available and mTOR kinase is active, MAF1 is hyperphosphorylated and RNA polymerase III is engaged in transcription. Stress-induced MAF1 dephosphorylation results in nuclear localization, increased targeting of gene-bound RNA polymerase III and a decrease in the transcriptional readout. Additionally, may also regulate RNA polymerase I and RNA polymerase II-dependent transcription through its ability to regulate expression of the central initiation factor TBP.

Nucleus. Cytoplasm.

MAF1 family

Transcription

Homolog of yeast MAF1; maf1; MAF1 homolog (S. cerevisiae); MAF1 homolog; MAF1_HUMAN; MGC20332; MGC31779; MGC39758; Repressor of RNA polymerase III transcription MAF1 homolog

This gene encodes a protein that is similar to Maf1, a Saccharomyces cerevisiae protein highly conserved in eukaryotic cells. Yeast Maf1 is a negative effector of RNA polymerase III (Pol III). It responds to changes in the cellular environment and represses pol III transcription. Biochemical studies identified the initiation factor TFIIIB as a target for Maf1-dependent repression.