THE OCULOCEREBRORENAL SYNDROME GENE-PRODUCT IS A 105-KD PROTEIN LOCALIZED TO THE GOLGI-COMPLEX

The oculocerebrorenal syndrome of Lowe (OCRL) is a multisystem disorde r affecting the lens, kidney, and CNS. The predicted amino acid sequen ce of the OCRL gene, OCRL-1, was used to develop antibodies against th e OCRL-1 protein. Western blot analysis using affinity-purified serum against the amino terminus of the OCRL-1 gene product (ocrl-1) demonst rates a single protein of 105 kD in fibroblasts of a normal individual that is absent in fibroblasts of an OCRL patient who lacks OCRL-1 tra nscript. A single protein with the same electrophoretic mobility is fo und by western analysis in various human cultured cell lines, and appr oximately the same size protein is also found in all mouse tissues tes ted. Northern analysis of various human and mouse tissues demonstrate that OCRL-1 transcript is expressed in nearly all tissues examined. By immunofluorescence, the ocrl-1 antibody stains a juxtanuclear region in normal fibroblast cells, while no specific staining is evident in t he OCRL patient who produces no transcript. Colocalization of the ocrl -1 protein to the Golgi complex was demonstrated using a known monoclo nal antibody against a Golgi-specific coat protein, beta-COP (beta coa tomer protein).