[HTML][HTML] Sumoylation regulates the transcriptional activity of MafA in pancreatic β cells

C Shao, MH Cobb - Journal of biological chemistry, 2009 - ASBMB
MafA is a transcriptional regulator expressed primarily in pancreatic β cells. It binds to the
RIPE3b/C1-binding site within the ins gene promoter, which plays a critical role in regulating
ins gene expression in response to glucose. Here, we show that MafA is post-translationally
modified by the small ubiquitin-related modifiers SUMO-1 and-2. Mutation of a single site in
MafA, Lys 32, blocks its sumoylation in β cells. Incubation of β cells in low glucose (2 mm) or
exposure to hydrogen peroxide increases sumoylation of endogenous MafA. Forced …