MAF1 Homolog (MAF1)

MAF1 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.MAF1 targeted an ELK1-binding site in the TBP promoter, and binding at this site was reciprocal with that of ELK1. Similarly, MAF1 occupancy of pol III genes was inversely correlated with that of the initiation factor TFIIIB and pol III. The phenotypic consequences of reducing MAF1 expression included changes in cell morphology and accumulation of actin stress fibers, whereas MAF1 overexpression suppressed anchorage-independent growth.