Paul M F, Velours J, Arselin de Chateaubodeau G, Aigle M, Guerin B
Institut de Biochimie Cellulaire et Neurochimie du Centre National de la Recherche Scientifique, Université de Bordeaux, France.
Eur J Biochem. 1989 Oct 20;185(1):163-71. doi: 10.1111/j.1432-1033.1989.tb15098.x.
The yeast nuclear gene ATP4, encoding the ATP synthase subunit 4, was disrupted by insertion into the middle of it the selective marker URA3. Transformation of the Saccharomyces cerevisiae strain D273-10B/A/U produced a mutant unable to grow on glycerol medium. The ATP4 gene is unique since subunit 4 was not present in mutant mitochondria; the hypothetical truncated subunit 4 was never detected. ATPase was rendered oligomycin-insensitive and the F1 sector of this mutant appeared loosely bound to the membrane. Analysis of mitochondrially translated hydrophobic subunits of F0 revealed that subunits 8 and 9 were present, unlike subunit 6. This indicated a structural relationship between subunits 4 and 6 during biogenesis of F0. It therefore appears that subunit 4 (also called subunit b in beef heart and Escherichia coli ATP synthases) plays at least a structural role in the assembly of the whole complex. Disruption of the ATP4 gene also had a dramatic effect on the assembly of other mitochondrial complexes. Thus, the cytochrome oxidase activity of the mutant strain was about five times lower than that of the wild type. In addition, a high percentage of spontaneous rho- mutants was detected.
酵母核基因ATP4编码ATP合酶亚基4，通过将选择标记URA3插入其中部使其失活。用其转化酿酒酵母菌株D273 - 10B/A/U产生了一个无法在甘油培养基上生长的突变体。ATP4基因很独特，因为突变线粒体中不存在亚基4；从未检测到假设的截短亚基4。ATP酶对寡霉素不敏感，该突变体的F1区段似乎与膜松散结合。对F0的线粒体翻译疏水亚基分析表明，与亚基6不同，亚基8和9存在。这表明在F0生物合成过程中亚基4和6之间存在结构关系。因此，亚基4（在牛心和大肠杆菌ATP合酶中也称为亚基b）似乎在整个复合物的组装中至少起结构作用。ATP4基因的破坏对其他线粒体复合物的组装也有显著影响。因此，突变菌株的细胞色素氧化酶活性比野生型低约五倍。此外，检测到高比例的自发rho - 突变体。
