Phosphatase Family LMWPTP

Phosphatase Classification: Superfamily Cys-based III: Family LMWPTP

Evolution

The LMWPTP is present not only in eukaryotes but also prokaryotes. In eukaryotes, it is generally absent from alveolates, trypanosoma, leishmania.

Domain Structure

Most LMWPTP consist almost entirely of a phosphatase domain

Function

In eukaryotes, LMWPTP dephosphorylates many receptor tyrosine kinases, such PDGFR, InsR, and Eph [1]. It is a substrate for Src and Src phosphorylation creates a Grb2 SH2 domain-binding site. Accordingly it has been implicated in cancer progression [2]. Polymorphisms have also been implicated in metabolic and immune diseases.

Human LMWPTP is also known to be a declycating agent, removing ribulose 5-phosphate from proteins [3, 4], in collaboration with Fructosamine Kinase.

Yeast lacks classical TKs but the least homolog (LTP1) is a tyrosine-specific phosphatase and may dephosphorylate the immunophilin Fpr3 in vivo [5], on a residue likely phosphorylated by CK2 [6].

In prokaryotes, the molecular function is not fully understood. It is involved in the syntheisis and translocation of exopolysaccharides (EPS) and capsular polysaccharides (CPS) in E. coli. YwlE also acts as an arginine phosphatase [7]

Reference

Error fetching PMID 20967558:
Error fetching PMID 23584899:
Error fetching PMID 23838530:
Error fetching PMID 17472574:
Error fetching PMID 12167657:
Error fetching PMID 15358193:
Error fetching PMID 9148902: