Cloning, Heterologous Expression, and Chromosomal Localization of Human Inositol Polyphosphate 1-Phosphatase

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 90; no. 12; pp. 5833 - 5837
• Main Authors: York, John D., Veile, Rosalie Ann, Donis-Keller, Helen, Majerus, Philip W.
• Format: Journal Article
• Language: English
• Published: Washington, DC National Academy of Sciences of the United States of America 15-06-1993; National Acad Sciences; National Academy of Sciences
• Subjects: 3T3 Cells; Amino Acid Sequence; Amino acids; Animals; Base Sequence; Biochemistry; Biological and medical sciences; Blotting, Northern; Cattle; cDNA; Cell Line; Cell lines; chromosome 2; Chromosome Mapping; Chromosomes, Human, Pair 2; Cloning, Molecular; Complementary DNA; COS cells; DNA; Escherichia coli - genetics; Fundamental and applied biological sciences. Psychology; gene mapping; Genes; Genes. Genome; Genetics; Humans; inositol-1,4-bisphosphate 1-phosphatase; Inositols; Karyotyping; man; Medical research; Mental disorders; Messenger RNA; Mice; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; nucleotide sequence; Oligodeoxyribonucleotides; Phosphates; Phosphoric Monoester Hydrolases - biosynthesis; Phosphoric Monoester Hydrolases - genetics; Phosphoric Monoester Hydrolases - metabolism; Polymerase Chain Reaction - methods; Polyphosphates; predictions; Restriction Mapping; Sequence Homology, Amino Acid; Somatic cells; Transfection; Ungulates; Genetic mapping; Human; Complementary DNA; Enzyme; A2-Chromosome; Molecular cloning; Gene expression
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.90.12.5833

Inositol polyphosphate 1-phosphatase, an enzyme in the phosphatidylinositol signaling pathway, catalyzes the hydrolysis of the 1 position phosphate from inositol 1,3,4-trisphosphate and inositol 1,4-bisphosphate. We used a cDNA that encodes bovine inositol polyphosphate 1-phosphatase as a probe to isolate the human counterpart by low-stringency hybridization. The 1.74-kb human cDNA has 341 bp of 5' untranslated region, 180 bp of 3' untranslated region, poly(A)32, and predicts a protein of 399 amino acids. Human and bovine inositol polyphosphate 1-phosphatases show 84% amino acid sequence identity. Northern blot analysis from a variety of human tissues demonstrates that a 1.9-kb mRNA is ubiquitously expressed with highest levels in pancreas and kidney. Several higher molecular weight mRNAs also are expressed in brain, muscle, heart, and liver. We have confirmed the functional identity of the human cDNA by heterologous expression in NIH 3T3 fibroblasts, COS-7 cells and Escherichia coli. Polymerase chain reaction assay of a panel of human-rodent somatic cell hybrid DNA using human inositol polyphosphate 1-phosphatase-specific DNA primers resulted in amplification of a specific product using chromosome 2 DNA as template. Fluorescence in situ hybridization of metaphase chromosomes localizes the gene to chromosome 2 band q32. The identification of the human inositol polyphosphate 1-phosphatase gene locus provides a target for linkage analysis to identify defects in patients with inherited psychiatric disorders that respond to lithium ions, an inhibitor of the enzyme.