Target Information

PGP9.5 (Protein gene product 9.5, UCH-L1, PARK5) is a neuron specific protein, structurally and immunologically distinct from neuron specific enolase. PGP9.5 has a molecular weight of 27 kDa and was first identified by high resolution two dimensional PAGE. PGP9.5 is a member of ubiquitin carboxyl-terminal hydrolase family 1 (peptidase family C12) with a ubiquitin carboxyl-terminal hydrolase domain. PGP9.5 is well known for having ubiquitin hydrolase and ligase activities that hydrolyzes small C-terminal adducts of ubiquitin to generate ubiquitin monomers. PGP9.5 is present in neurons and nerve fibers at all levels of the central and peripheral nervous system, in neuroendocrine cells, in segments of the renal tubules, in spermatogonia and Leydig cells of the testis, in ova and in some cells of both the pregnant and non-pregnant corpus luteum. Over expression of PGP9.5 leads to non-small cell lung cancer while decreased expression leads to Huntington disease and Alzheimer disease. Since PGP9.5 is present in cellular inclusions, it can be a useful as a neuronal marker and in the studies of neurodegenerative disorders such as with Parkinson disease.