Phosphatase Subfamily PPPRK TN

Phosphatase Classification: Fold CC1:Superfamily CC1: Family PTP: Subfamily PTPRK (R2B): Technical notes

PTPRK has four members in human, with orthologs across the vertebrates. PTPRK is also found in invertebrate chordates

• Ciona intestinalis (XP_002125715.3) has a full length prediction with the typical MAM-Ig-Fn3-Fn3-Fn3 -PTP-PTP architecture
• Oikopleura dioca (CBY08646.1) has a MAM-Ig-FN3(2)-PTP(3) architecture, with one more PTP domain than typical.

Putative homologs of PTPRK are present in other invertebrates, but they have different domain architectures and their orthology to PTPRK is uncertain. These include:

PTP36E is similar to PTPRK but most or all members have lost their extracellular regions.

KRCS

This putative new subfamily is found in molluscs, and has a extracellular region with a Kringle domain, a CS-rich domain and some have a SKG6 transmembrane domain. Members include:

• KRCS-Acal (|XP_012937090.1) from Aplysia californica
• KRCS_Bgla: with a KR-EGF_Lam-SKG6-PTP(2) architecture from Biomphalaria glabrata.
• KRCS_Cgig (|EKC20265.1) from Crassostrea gigas