细胞色素c氧化酶亚基VIb编码cDNA的分离及不同组织中coxVIb mRNA的稳态水平

Isolation of cDNAs encoding subunit VIb of cytochrome c oxidase and steady-state levels of coxVIb mRNA in different tissues.

作者信息

Taanman J W, Schrage C, Ponne N J, Das A T, Bolhuis P A, de Vries H, Agsteribbe E

机构信息

Laboratory of Physiological Chemistry, University of Groningen, The Netherlands.

出版信息

Gene. 1990 Sep 14;93(2):285-91. doi: 10.1016/0378-1119(90)90237-l.

DOI:10.1016/0378-1119(90)90237-l

PMID:2172092

Abstract

A full-length cDNA clone specifying the nuclear-encoded subunit VIb of human cytochrome c oxidase (COX) was isolated from a human skeletal muscle cDNA expression library. This was done with antiserum directed against the group of subunits VIa, b and c of bovine heart COX. A potential ribosome-binding site was located immediately upstream from the initiation codon. The predicted amino acid sequence revealed 85% similarity with the corresponding subunit of bovine heart COX. Subunit VIb lacks a cleavable presequence for mitochondrial addressing. We assume that there are no tissue-specific isoforms of subunit VIb, since (i) in a Northern blot experiment a single hybridizing band of approx. 500 nucleotides was demonstrated in RNA from liver, skeletal muscle, MOLT-4 cells and fibroblasts and (ii) a full-length cDNA clone with an identical sequence was isolated from a human liver cDNA library. Steady-state levels of the coxVIb transcript were different in the tissues examined.

摘要

从人骨骼肌cDNA表达文库中分离出一个全长cDNA克隆，该克隆编码人细胞色素c氧化酶（COX）的核编码亚基VIb。这是通过针对牛心COX亚基VIa、b和c的抗血清完成的。在起始密码子上游紧邻位置发现了一个潜在的核糖体结合位点。预测的氨基酸序列与牛心COX的相应亚基显示出85%的相似性。亚基VIb缺乏用于线粒体定位的可裂解前导序列。我们推测不存在亚基VIb的组织特异性同工型，因为：（i）在Northern印迹实验中，在来自肝脏、骨骼肌、MOLT-4细胞和成纤维细胞的RNA中显示出一条约500个核苷酸的单一杂交带；（ii）从人肝脏cDNA文库中分离出一个具有相同序列的全长cDNA克隆。在所检测的组织中，coxVIb转录本的稳态水平有所不同。