Difference between revisions of "Phosphatase Subfamily PTPRA"

Revision as of 22:46, 10 December 2014

Phosphatase Classification: Superfamily CC1: Family PTP: Subfamily PTPRA

This is a stub!! Excuse the mess.

PTPRA is a vertebrate-specific receptor PTP subfamily

Evolution

PTPRA and PTPRE are related human genes with homologs across vertebrates. No conclusive invertebrate homologs have been found, though the phosphatase domains are most similar to the invertebrate Ptp69D subfamily.

Domain Structure

All members have twin intracellular PTP phosphatase catalytic domains and a conserved juxtamembrane region of ~90 AA between the transmembrane region and the first PTP domain. Both have short, poorly conserved extracellular regions and neither are known to bind ligand. In human PTPRA, the extracellular region is 132 AA long, has poor conservation even between mammals and fish and low sequence complexity. NCBI CDD annotates it weakly as an endomucin domain, a region found in several surface-expressed endothelial proteins (Pfam: PF07010 [1]). No sequence similarity is seen to any protein other than vertebrate PTPRA. PTPRE has multiple splice forms, including one with an alternative N-terminus that lacks a signal peptide, and one with a 26 AA extracellular region, which is also poorly conserved between vertebrate homologs. The intracellular juxtamembrane region (upstream of the PTP domains) of ~88 AA is highly conserved between vertebrate homologs.

An additional splice form of PTPRE has been reported, which replaces the second PTP domain with a unique tail [1]

Functions

To be added

References

1. Wabakken T, Hauge H, Funderud S, and Aasheim HC. Characterization, expression and functional aspects of a novel protein tyrosine phosphatase epsilon isoform. Scand J Immunol. 2002 Sep;56(3):276-85. DOI:10.1046/j.1365-3083.2002.01127.x | PubMed ID:12193229 | HubMed [Wabakken]