TY - JOUR
T1 - Cell lines from kidney proximal tubules of a patient with Lowe syndrome lack OCRL inositol polyphosphate 5-phosphatase and accumulate phosphatidylinositol 4,5-bisphosphate
AU - Zhang, Xiaoling
AU - Hartz, Patricia A.
AU - Philip, Elizabeth
AU - Racusen, Lorraine C.
AU - Majerus, Philip W.
PY - 1998/1/16
Y1 - 1998/1/16
N2 - The protein product of the gene that when mutated is responsible for Lowe syndrome, or oculocerebrorenal syndrome (OCRL), is an inositol polyphosphate 5-phosphatase. It has a marked preference for phosphatidylinositol 4,5-bisphosphate although it hydrolyzes all four of the known inositol polyphosphate 5-phosphatase substrates: inositol 1,4,5- trisphosphate, inositol 1,3,4,5-tetrakisphosphate, phosphatidylinositol 4,5- bisphosphate, and phosphatidylinositol 3,4,5-trisphosphate. The enzyme activity of this protein is determined by a region of 672 out of a total of 970 amino acids that is homologous to inositol polyphosphate 5-phosphatase II. Cell lines from kidney proximal tubules of a patient with Lowe syndrome and a normal individual were used to study the function of OCRL. The cells from the Lowe syndrome patient lack OCRL protein. OCRL is the major phosphatidylinositol 4,5-bisphosphate 5-phosphatase in these cells. As a result, these cells accumulate phosphatidylinositol 4,5-bisphosphate even though at least four other inositol polyphosphate 5-phosphatase isozymes are present in these cells. OCRL is associated with lysosomal membranes in control proximal tubule cell lines suggesting that OCRL may function in lysosomal membrane trafficking by regulating the specific pool of phosphatidylinositol 4,5-bisphosphate that is associated with lysosomes.
AB - The protein product of the gene that when mutated is responsible for Lowe syndrome, or oculocerebrorenal syndrome (OCRL), is an inositol polyphosphate 5-phosphatase. It has a marked preference for phosphatidylinositol 4,5-bisphosphate although it hydrolyzes all four of the known inositol polyphosphate 5-phosphatase substrates: inositol 1,4,5- trisphosphate, inositol 1,3,4,5-tetrakisphosphate, phosphatidylinositol 4,5- bisphosphate, and phosphatidylinositol 3,4,5-trisphosphate. The enzyme activity of this protein is determined by a region of 672 out of a total of 970 amino acids that is homologous to inositol polyphosphate 5-phosphatase II. Cell lines from kidney proximal tubules of a patient with Lowe syndrome and a normal individual were used to study the function of OCRL. The cells from the Lowe syndrome patient lack OCRL protein. OCRL is the major phosphatidylinositol 4,5-bisphosphate 5-phosphatase in these cells. As a result, these cells accumulate phosphatidylinositol 4,5-bisphosphate even though at least four other inositol polyphosphate 5-phosphatase isozymes are present in these cells. OCRL is associated with lysosomal membranes in control proximal tubule cell lines suggesting that OCRL may function in lysosomal membrane trafficking by regulating the specific pool of phosphatidylinositol 4,5-bisphosphate that is associated with lysosomes.
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U2 - 10.1074/jbc.273.3.1574
DO - 10.1074/jbc.273.3.1574
M3 - Article
C2 - 9430698
AN - SCOPUS:0031914642
SN - 0021-9258
VL - 273
SP - 1574
EP - 1582
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 3
ER -