Oculocerebrorenal Syndrome Of Lowe (OCRL)

The OCRL gene encodes a phosphatidylinositol 4,5-bisphosphate-5-phosphatase localized to the trans-Golgi network that is involved in actin polymerization. This cDNA encoded amino acids 264 through 968 of the OCRL protein. Recombinant OCRL protein hydrolyzed phospholipid substrate 10- to 30-fold better than 5-phosphatase II, and 5-phosphatase I did not cleave the lipid at all. OCRL functions as a phosphatidylinositol 4,5-bisphosphate 5-phosphatase in OCRL-expressing Sf9 cells. The results suggested that OCRL is mainly a lipid phosphatase that may control cellular levels of a critical metabolite, phosphatidylinositol 4,5-bisphosphate. Deficiency of this enzyme apparently causes the protean manifestations of Lowe syndrome.