Zeta’s rabbit monoclonal atnibody reacts with PGP9.5, a soluable protein of 20-30kDa also known as ubiquitin carboxyl-terminal hydrolase-1 (UCHL1). Immunostaining for PGP9.5 has been shown in a wide variety of mesenchymal neoplasms . A mutation in PGP9.5 gene is believed to cause a form of Parkinson’s disease. PGP 9.5 was isolated from brain and is a general marker for neuronal and neuroendocrine tissue. Before the discovery of PGP9.5, neurone specific enolase (NSE) has been the only general marker for the paracrine system and tumours derived from it. Staining for PGP 9.5 is a valuable additional probe in the exploration of the paracrine system and the diagnosis of tumours arising from it. PGP9.6 IHC staining has found widespread application in the detection of fine nerves in peripheral tissues of many vertebrate species.
PGP9.5 was first detected as a brain-specific protein decades ago. The protein is highly conserved and localized in neurones and neuroendocrine cells in vertebrates, forming an estimated 5-10% of cytoplasmic protein. A few specialised neurones lack PGP9.5 and possibly replaceable neurones have low levels of the protein. PGP9.5 shows an unusual highly knotted structure with five “crossovers” but there are differences in substrate specificity, amino-acid sequence, and tissue distribution between them.
Isolated loss of UCHL1/PGP 9.5 function seen in the gracile axonal dystrophy (GAD) mouse due to a deletion in its gene results in a failure of axonal transport and a “dying-back” axonopathy beginning distally in long axons.