Cloning, heterologous expression, and chromosomal localization of human inositol polyphosphate 1-phosphatase.
Cloning, heterologous expression, and chromosomal localization of human inositol polyphosphate 1-phosphatase.
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人肌醇多磷酸1-磷酸酶的克隆、异源表达和染色体定位。
DOI：
10.1073/pnas.90.12.5833
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发表时间：
1993
影响因子：
11.1
通讯作者：
Majerus,PW
中科院分区：
文献类型：
--
作者：
York,JD;Veile,RA;Donis-Keller,H;Majerus,PW
肌醇多聚磷酸1-磷酸酶是磷脂酰肌醇信号转导途径中的一种酶，催化1，3，4-三磷酸和1，4-二磷酸肌醇的1位磷酸水解酶。我们以编码牛肌醇多聚磷酸1-磷酸酶的基因为探针，通过低严格率杂交的方法分离出人的同源基因。该基因全长1.74kb，5‘非翻译区341个核苷酸，3’非翻译区180个碱基对，Poly(A)32个核苷酸，编码399个氨基酸。人和牛的肌醇多聚磷酸1-磷酸酶具有84%的氨基酸序列同源性。Northern印迹分析表明，1.9kb的mRNA在各种人体组织中普遍表达，在胰腺和肾脏中的表达水平最高。在脑、肌肉、心脏和肝脏中也表达了几个较高分子量的mRNAs。我们通过在NIH3T3成纤维细胞、COS-7细胞和大肠杆菌中的异源表达，证实了人cDNAs的功能一致性。用人肌醇多磷酸1-磷酸酶特异的DNA引物对一组人-啮齿动物体细胞杂交DNA进行聚合酶链式反应分析，以2号染色体DNA为模板扩增出特定的产物。中期染色体荧光原位杂交将该基因定位于染色体2带q32。人类肌醇多聚磷酸1-磷酸酶基因座的鉴定为连锁分析提供了一个目标，以确定遗传性精神障碍患者对该酶的抑制剂锂离子的反应缺陷。
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.