Rev-erbA beta, a NR1 Thyroid Hormone-Like Receptor, has been shown to affect cell proliferation, organ physiology, and myogenesis. Rev-erbA beta has been shown to be a constitutive repressor and binds as a monomer or homodimer to target DNA, such as the n-myc gene. Rev-erbA beta has also been shown to repress the human apoCIII gene, therefore underscoring a physiological role in the regulation of genes involved in triglyceride metabolism and the pathogenesis of atherosclerosis. Two isoforms of Rev-erbA beta have been isolated in rats (ReverbA beta 1 and Rev-erbA beta 2). Rev-erbA beta 2 is longer than Rev-erbA beta 1 by 195 amino acids..