Genomic cloning, molecular characterization, and functional analysis of human CLCA1, the first human member of the family of Ca2+-activated Cl- channel proteins
Genomic cloning, molecular characterization, and functional analysis of human CLCA1, the first human member of the family of Ca2+-activated Cl- channel proteins
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DOI：
10.1006/geno.1998.5562
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发表时间：
1998-12-01
期刊：
影响因子：
4.4
通讯作者：
Pauli, BU
中科院分区：
文献类型：
--
作者：
Gruber, AD;Elble, RC;Pauli, BU
我们已经克隆了第一个人类钙激活氯离子通道家族成员，人（h）CLCA 1，并对其进行了分子和功能表征。该31，902-bp基因位于染色体1 p22 -31上，并且之前是包含L1转座元件的规范启动子区域。与其他物种中所有先前已知的同源物相比，hCLCA 1仅在肠基底隐窝上皮和杯状细胞中表达，这表明它不代表其中任何一种的人类对应物。在HEK 293细胞中表达914个氨基酸的hCLCA 1蛋白产生了一个125 kDa的前体，该前体被加工产生两个细胞表面相关的亚基，一个90 kDa的蛋白和一组37至41 kDa的蛋白。在90 kDa亚基内建立了四个跨膜结构域。用CLCA 1转染的HEK 293细胞表现出全细胞Ca 2+敏感性Cl-电流的增加，该电流被向外整流并被4，4 '-二异硫氰基芪-2，2'-二磺酸、二硫苏糖醇和尼氟灭酸抑制。转染细胞的细胞贴附贴片记录显示斜率电导为13.4 pS的单通道。这些发现表明，人CLCA 1介导人肠道中Ca 2+激活的Cl-传导，使其成为囊性纤维化发病机制中调节因子的有趣候选者。(C)北京：科学出版社.
We have cloned and molecularly and functionally characterized the first human member of the family of Ca2+-activated Cl- channels, human (h) CLCA1. The 31,902-bp gene is located on chromosome 1p22-31 and is preceded by a canonic promoter region that contains an L1 transposable element. In contrast to all previously known homologs in other species, hCLCA1 is exclusively expressed in intestinal basal crypt epithelia and goblet cells, suggesting that it does not represent the human counterpart of any of them. Expression of the 914-amino-acid hCLCA1 protein in HEK 293 cells yielded a 125-kDa precursor that was processed to yield two cell-surface-associated subunits, a 90-kDa protein and a group of 37- to 41-kDa proteins. Four transmembrane domains were established within the 90-kDa subunit. HEK 293 cells transfected with CLCA1 exhibited an increase in whole-cell Ca2+-sensitive Cl- currents that were outwardly rectified and inhibited by 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid, dithiothreitol, and niflumic acid. Cell-attached patch recordings of transfected cells revealed single channels with a slope conductance of 13.4 pS. These findings suggest that human CLCA1 mediates a Ca2+-activated Cl- conductance in the human intestine and make it an interesting candidate as a modulating factor in the pathogenesis of cystic fibrosis. (C) 1998 Academic Press.