编码Na +，K + -ATP酶A3亚型的mRNA的组织特异性、在脑中的定位及无细胞翻译

Tissue specificity, localization in brain, and cell-free translation of mRNA encoding the A3 isoform of Na+,K+-ATPase.

作者信息

Schneider J W, Mercer R W, Gilmore-Hebert M, Utset M F, Lai C, Greene A, Benz E J

机构信息

Department of Human Genetics, Yale University School of Medicine, New Haven, CT 06510.

出版信息

Proc Natl Acad Sci U S A. 1988 Jan;85(1):284-8. doi: 10.1073/pnas.85.1.284.

The isolation of multiple Na+,K+-ATPase cDNAs from rat brain has led to the discovery of a family of alpha-isoform genes. Using A1 (alpha), A2 (alpha+), and A3 (alpha III) Na+,K+-ATPase gene probes, we have analyzed the distribution of Na+,K+-ATPase mRNAs in adult and fetal rat tissues by RNA blot and hybridization histochemistry. A1 Na+,K+-ATPase mRNA was found ubiquitously among various tissues, with highest levels in transport epithelial and neural tissues. A2 mRNA was found in adult neural and muscle tissues, and A3 mRNA was found only in neural tissues and fetal heart muscle. Both A1 and A2 mRNAs were less abundant in fetal brain than in adult brain; in contrast, A3 mRNA was abundant at both stages. In situ mapping of brain areas that contain A3 mRNA suggests that this Na+,K+-ATPase isoenzyme is expressed predominantly by neural cells. Analysis of Na+,K+-ATPase proteins generated by cell-free translation of synthetic mRNAs suggests that the A3 protein has properties similar to A2 (alpha+).

从大鼠脑中分离出多个钠钾ATP酶cDNA，从而发现了一个α - 同工型基因家族。利用A1（α）、A2（α +）和A3（α III）钠钾ATP酶基因探针，我们通过RNA印迹和杂交组织化学分析了成年和胎鼠组织中钠钾ATP酶mRNA的分布。在各种组织中均普遍发现A1钠钾ATP酶mRNA，在转运上皮组织和神经组织中水平最高。A2 mRNA存在于成年神经和肌肉组织中，而A3 mRNA仅在神经组织和胎儿心肌中发现。与成年脑相比，胎儿脑中A1和A2 mRNA的丰度均较低；相反，A3 mRNA在两个阶段均很丰富。对含有A3 mRNA的脑区进行原位定位表明，这种钠钾ATP酶同工酶主要由神经细胞表达。对合成mRNA进行无细胞翻译产生的钠钾ATP酶蛋白的分析表明，A3蛋白具有与A2（α +）相似的特性。