NGFI-A Binding Protein 1 (NAB1)

NAB1 binds the inhibitory domain of NGFIA and inhibits the ability of NGFIA to activate transcription. NAB1 also represses Krox20 activity, but it does not influence Egr3 or NGFIC, thus providing a mechanism for the differential regulation of this family of immediate-early transcription factors.

Nab1 was expressed in the nuclei of mouse cardiac myocytes, endothelial cells, and fibroblasts. Pressure overload induced by transverse aortic constriction increased Nab1 expression in the left ventricular myocardium. NAB1 expression was increased about 2.5-fold in left ventricles from failing human hearts compared with nonfailing hearts.