Phosphatase Subfamily PTPRD

Phosphatase Classification: Fold CC1: Superfamily CC1: Family PTP: Subfamily PTPRD

PTPRC (CD45) is a vertebrate-specific receptor PTP involved in immune signaling.

Evolution

PTPRD subfamily is found in holozoan (metazoan plus it closest relative choanoflagellate). PTPRD subfamily has three gene members in most vertebrates: PTPRD, PTPRF and PTPRS. It has single member in most invertebrate metazoan. Interestingly, it greatly expanded in sponge.

Domain Structure

All three members of PTPRD subfamily in human has twin intracellular PTP phosphatase domains, and extracellular Ig domains and FN3 domains. Each of them have multiple alternative splicing isoforms.

Functions

CD45 modulates immune function [1]. It is selectively expressed on lymphocytes and dephosphorylates and activates the src family tyrosine kinases lck, fyn and lyn in B and T cells.

References

1. Furlan G, Minowa T, Hanagata N, Kataoka-Hamai C, and Kaizuka Y. Phosphatase CD45 both positively and negatively regulates T cell receptor phosphorylation in reconstituted membrane protein clusters. J Biol Chem. 2014 Oct 10;289(41):28514-25. DOI:10.1074/jbc.M114.574319 |