Basic helix-loop-helix (bHLH) proteins are a group of transcription factors that influence the regulation of neurogenesis, cardiogenesis, myogenesis, differentiation and cell proliferation. p60TRP (p60-transcription-regulator-protein), also known as BHLHb9 (basic helix-loop-helix domain containing, class B, 9) or p60-like protein, is a 547 amino acid cytoplasmic and nuclear protein that belongs to the GPRASP family. A few members of the GRASP family are considered G protein-coupled receptors that play a role in many different stimulus-response pathways. Highly expressed in brain, p60TRP may be involved in the control of cellular aging and survival. In colon cancer cells, p60TRP is down regulated due to CpG hypermethylation of its promoter, and patients suffering from Alzheimer disease have low levels of p60TRP. p60TRP binds to karyopherin ∫3, also known as Ran BP-5, and protein-phosphatase-2A (PP2A), and is encoded by a gene located on human chromosome Xq22.1.