Mediates transcriptional repression by certain nuclear receptors. Plays a role in development and neuronal function. May play a role in muscle-specific oxidative mitochondrial metabolism. Interacts with gex-3. Interacts (via C-terminus) with nhr-60. In larvae, expressed in pharyngeal neurons, ventral and dorsal nerve cords, tail neurons, egg-laying neurons and egg-laying muscles. Detected in the neurons of the pharyngeal nerve ring, head neurons, tail neurons and egg-laying muscles in adults. Detected in male-specific tail ganglia and rays in males. Expressed throughout the developmental stages with a 2-fold increase in late larval (L4) stage. Mutant animals display a progressive defect in locomotion starting at the L2 stage, showing delayed response to prodding, irregular thrashing movements and a low pharyngeal pumping rate. Worms have shorter body length, convoluted intestine and develop gonadogenesis defects including loss of spermathecae, sterility and larval arrest at L4 stage. They also show abnormal cholinergic signaling leading to early onset of paralysis in the presence of aldicarb, an acetylcholinesterase inhibitor. RNAi-mediated knockdown results in enlargement of mitochondria in the body wall muscle. Muscle-specific knockdown shows an increased level of oxygen consumption. Belongs to the N-CoR nuclear receptor corepressors family.