Nicotinamide adenine dinucleotide-induced multimerization of the co-repressor CtBP1 relies on a switching tryptophan.

ABSTRACT: The transcriptional co-repressor C-terminal binding protein (CtBP) interacts with a number of repressor proteins and chromatin modifying enzymes. How the biochemical properties including binding of dinucleotide, oligomerization, and dehydrogenase domains of CtBP1 direct the assembly of a functional co-repressor to influence gene expression is not well understood. In the current study we demonstrate that CtBP1 assembles into a tetramer in a NAD(H)-dependent manner, proceeding through a dimeric intermediate. We find that NAD-dependent oligomerization correlates with NAD(+) binding affinity and that the carboxyl terminus is required for assembly of a dimer of dimers. Mutant CtBP1 proteins that abrogate dinucleotide-binding retain wild type affinity for the PXDLS motif, but do not self-associa

SUBMITTER: Madison DL 

PROVIDER: S-EPMC3784699 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature