Supercomplex-associated Cox26 protein binds to cytochrome c oxidase.
Supercomplex-associated Cox26 protein binds to cytochrome c oxidase.
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超复合物相关的 Cox26 蛋白与细胞色素 c 氧化酶结合。
DOI：
10.1016/j.bbamcr.2016.04.012
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Wittig,Ilka
中科院分区：
文献类型：
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作者：
Strecker,Valentina;Kadeer,Zibirnisa;Heidler,Juliana;Cruciat,Cristina-Maria;Angerer,Heike;Giese,Heiko;Pfeiffer,Kathy;Stuart,RosemaryA;Wittig,Ilka
在这里，我们鉴定了一个疏水的6.4 kDa蛋白，Cox26，作为酵母线粒体超复合体的一个新组成部分，包括呼吸复合体III和IV。多维天然和变性电泳技术用于鉴定与Cox26相互作用的蛋白。大多数Cox26蛋白被发现与III-IV超复合物的复合物IV部分非共价结合。在复合体IV的Cox2亚基上观察到一个Cox26群体以二硫键伙伴关系存在。没有观察到Cox26缺乏的明显生长表型，这表明Cox26可能在COX酶学中不起关键作用，我们推测Cox26可能起到调节或支持Cox2蛋白的作用。呼吸超复合体是在缺乏Cox26蛋白的情况下组装的，但它们的模式与野生型III-IV型超复合体的外观略有不同。只要在正常生长条件下培养细胞，观察到配合物III和IV的催化活性正常，呼吸作用与野生型相当。当Cox26蛋白缺失时，应激条件（如高温）会导致非发酵培养基中呼吸作用的轻度减少。
Here we identified a hydrophobic 6.4 kDa protein, Cox26, as a novel component of yeast mitochondrial supercomplex comprising respiratory complexes III and IV. Multi-dimensional native and denaturing electrophoretic techniques were used to identify proteins interacting with Cox26. The majority of the Cox26 protein was found non-covalently bound to the complex IV moiety of the III–IV supercomplexes. A population of Cox26 was observed to exist in a disulfide bond partnership with the Cox2 subunit of complex IV. No pronounced growth phenotype for Cox26 deficiency was observed, indicating that Cox26 may not play a critical role in the COX enzymology, and we speculate that Cox26 may serve to regulate or support the Cox2 protein. Respiratory supercomplexes are assembled in the absence of the Cox26 protein, however their pattern slightly differs to the wild type III–IV supercomplex appearance. The catalytic activities of complexes III and IV were observed to be normal and respiration was comparable to wild type as long as cells were cultivated under normal growth conditions. Stress conditions, such as elevated temperatures resulted in mild decrease of respiration in non-fermentative media when the Cox26 protein was absent.