Phosphatase Subfamily PTPN1

Phosphatase Classification: Fold CC1: Superfamily CC1: Family PTP: Subfamily PTPN1

PTPN1 subfamily dephoshorylate kinases of various families, including Insulin receptor kinase (InsR), epidermal growth factor receptor kinase (EGFR), JAK (JAK2 and TYK2). The phosphatase emerged later than the related kinases. The phosphatase first emerged in Trichoplax. EGFR is conserved from sponge to human but lost in Trichoplax, and InsR is conserved from Trichoplax to human.

Evolution

PTPN1 subfamily emerged in animals, as it is found in most if not all eumetazoa, Porifera (e.g. sponge) and Placozoa (e.g. Trichoplax), but absent from Choanoflagellata (e.g. Monosiga) (for the phylogeny of animal at here). In human, there are two copies: PTPN1 (PTP1B) and PTPN2. The two copies can be traced back to the time when vertebrates emerged. The orthologs for each of them are found in most vertebrates from fish to primates, and there is a single copy in non-vertebrate metazoa.

It substrate EGFR is conserved from sponge to human but lost in Trichoplax, and InsR is conserved from Trichoplax to human.

(PS: Why PTPN1 and PTPN2 have different functions?)