Mani-Telang, P., Sutrias-Grau, M., Williams, G., Arnosti, D.N. (2007). Role of NAD binding and catalytic residues in the C-terminal binding protein corepressor.  FEBS Lett. 581(27): 5241--5246.

FBrf0201457

Research paper

CtBP corepressor proteins potentiate the activity of many metazoan transcriptional repressors. These proteins are homologous to prokaryotic D-2-hydroxyacid dehydrogenases, possessing an NAD/NADH binding fold and conserved active site residues. When expressed in Drosophila, a catalytic site mutant retains biological activity, however, we find that an NAD binding mutant lacks biological activity. The NAD mutant, similar to a dimerization mutant, is expressed at low levels, indicating that binding of NAD/NADH may affect CtBP stability. These data support the idea that the ancestral dehydrogenase activity is not required for CtBP function, and NAD binding may play a regulatory, rather than catalytic, role.