Cardazzo B, Hamel P, Sakamoto W, Wintz H, Dujardin G
Centre de Génétique Moléculaire, Gif sur Yvette, France.
Gene. 1998 Oct 9;221(1):117-25. doi: 10.1016/s0378-1119(98)00417-x.
The yeast Abc1 protein acts as a chaperone-like protein essential for the proper conformation and efficient functioning of the respiratory complex III. By functional complementation of a yeast abc1 mutant, we have identified an Arabidopsis thaliana cDNA that corresponds to a single copy gene and encodes a protein sharing 45% similarity with the yeast Abc1p protein. Cytochrome spectra and respiratory activity measurements have shown that the plant protein allows a partial restoration of the complex III activity. No major difference in the steady-state level of ABC1At mRNA was observed in various plant tissues, suggesting that ABC1At is constitutively expressed in A. thaliana. Phylogenetic analysis revealed that the Abc1At protein belongs to a large family of proteins composed of two eukaryotic and one prokaryotic subgroups differing by their degree of similarity and probably by their function.
酵母Abc1蛋白作为一种伴侣样蛋白，对呼吸复合体III的正确构象和高效功能至关重要。通过对酵母abc1突变体进行功能互补，我们鉴定出一个拟南芥cDNA，它对应一个单拷贝基因，编码一种与酵母Abc1p蛋白有45%相似性的蛋白质。细胞色素光谱和呼吸活性测量表明，该植物蛋白能使复合体III的活性部分恢复。在各种植物组织中未观察到ABC1At mRNA稳态水平的显著差异，这表明ABC1At在拟南芥中组成型表达。系统发育分析表明，Abc1At蛋白属于一个大家族的蛋白质，该家族由两个真核亚组和一个原核亚组组成，它们在相似程度上存在差异，可能在功能上也有所不同。
