Ichiro Okabe

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Lowe's oculocerebrorenal syndrome (OCRL) is a human X-linked developmental disorder of unknown pathogenesis and has a pleiotropic phenotype affecting the lens, brain and kidneys. The OCRL locus has been mapped to Xq25-q26 by linkage and by finding de novo X; autosome translocations at Xq25-q26 in two unrelated females with OCRL. Here we use yeast artificial(More)
We performed positional cloning of genes carried on yeast artificial chromosomes that span a human translocation breakpoint associated with a human disease and isolated by chance human and bovine genes with strong homology to the S. cerevisiae genes, SNF2/SWI2 and STH1, and the D. melanogaster gene brahma. We report here sequence analysis, expression data,(More)
Menkes disease (McKusick 309400) is an X-linked recessive disorder of copper (Cu) metabolism. An excessive amount of Cu accumulates in the kidney of patients with the disease (Danks, 1989). However, renal toxicity from Cu has not been noticed. We investigated the renal tubular function of four patients with classical Menkes disease. The patients were all(More)
An important class of phosphorylated phosphoinositides carrying a phosphate group at the 3' position of the inositol ring are generated by phosphoinositide 3-kinases (PI 3-kinases) which convert PtdIns, PtdIns(4)P, and PtdIns(4,5)P 2 to PtdIns(3)P, PtdIns(3,4)P2, and PtdIns(3,4,5)P 3 respectively (Frnman et al. 1998; Vanhaesebroeck et al. 2001). The PI(More)
The mitochondrial copper concentrations and cytochrome C oxidase activity of the fibroblasts from the patients with Menkes syndrome were investigated. Both the mitochondrial copper concentrations and cytochrome C oxidase activity of fibroblasts from patients with Menkes syndrome were lower than those of the control fibroblasts. These data indicate that the(More)
Phosphatidylinositol 3,4,5-trisphosphate is a phospholipid signaling molecule involved in many cellular functions including growth factor receptor signaling, cytoskeletal organization, chemotaxis, apoptosis, and protein trafficking. Phosphorylation at the 3 position of the inositol ring is catalyzed by many different 3-kinases (classified as types IA, IB,(More)
Deficiency of ornithine transcarbamylase (OTC, EC 2.1.3.3) (McKusick 31125), a mitochondrial enzyme of the urea cycle, appears to be one of the most frequent causes of inherited ammonia intoxication, and evidence indicates that the enzyme is X-linked. Recently, different kinds of mutation have been reported (Cathelineauet al., 1972; Briandet al., 1982). We(More)
A mouse inositol polyphosphate 1-phosphatase (Inpp1) cDNA fragment (348 bp) was amplified by means of the polymerase chain reaction using a mouse cDNA library as template with primers designed from published human and bovine cDNA sequences. We isolated a 1623-bp full-length Inpp1 cDNA from a mouse brain cDNA library using this amplified cDNA fragment as(More)
Sir: Dichloroacetate (DCA, 15-20 mg/kg per day) was given orally twice daily to a 12-mouth-old boy with congenital lactic acidosis [1, 3]. The clinical and laboratory findings were compatible with Leigh syndrome [2]. Enzyme activities associated with lactate metabolism were normal in his fibroblasts (Table 1). While blood lactate and pyruvate decreased from(More)
Ornithine transcarbamylase (OTC, EC 2.1.3.3), located in the mitochondriat matrix, is synthesized on membrane-free polysomes in the form of a larger precursor and is then proteolytically processed to the mature form. OTC deficiency, which is a disease with X-linked dominant inheritance, is caused by various kinds of mutation (Briand et al., 1982). We report(More)