phosphatidylinositide phosphatase SAC2 (sac domain-containing inositol phosphatase 2, sac domain-containing phosphoinositide 5-phosphatase 2, hSAC2, inositol polyphosphate 5-phosphatase F, INPP5F, KIAA0966, SAC2, MSTP007, MSTP047)

Function

• inositol 5-phosphatase which acts on phosphatidylinositol 4,5-bisphosphate & phosphatidylinositol 3,4,5-triphosphate
• hydrolyzes phosphatidylinositol 4,5-bisphosphate most effectively
• modulates AKT/GSK3B pathway by decreasing AKT & GSK3B phosphorylation

Kinetic parameters:

• KM=14.3 uM for Ptdins(4,5)P2 (at pH 6.0)

Structure

• contains 1 SAC domain
• inositol polyphosphate 5-phosphatases usually have 2 conserved motifs essential for 5-phosphatase activity; however, INPP5F does not contain such motifs, & phosphatase activity seems to exist in the SAC domain

Alternative splicing

named isoforms=3

Expression

ubiquitous

More general terms

• phosphomonoesterase
• phosphoprotein

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:2287
• UniProt: http://www.uniprot.org/uniprot/Q9Y2H2.html