Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan.
Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan.
Biochem Biophys Res Commun. 2014 Jan 17;443(3):997-1002. doi: 10.1016/j.bbrc.2013.12.084. Epub 2013 Dec 19.
Bcs1 is a transmembrane chaperone in the mitochondrial inner membrane, and is required for the mitochondrial Respiratory Chain Complex III assembly. It has been shown that the highly-conserved C-terminal region of Bcs1 including the AAA ATPase domain in the matrix side is essential for the chaperone function. Here we describe the importance of the N-terminal short segment located in the intermembrane space in the Bcs1 function. Among the N-terminal 44 amino acid residues of yeast Bcs1, the first 37 residues are dispensable whereas a hydrophobic amino acid in the residue 38 is essential for integration of Rieske Iron-sulfur Protein into the premature Complex III from the mitochondrial matrix. Substitution of the residue 38 by a hydrophilic amino acid residue affects conformation of Bcs1 and interactions with other proteins. The evolutionarily-conserved short α helix of Bcs1 in the intermembrane space is an essential element for the chaperone function.
Bcs1 是线粒体内膜上的一种跨膜伴侣蛋白，对于线粒体呼吸链复合物 III 的组装是必需的。已经表明，Bcs1 的高度保守的 C 端区域包括基质侧的 AAA ATP 酶结构域对于伴侣蛋白功能是必需的。在这里，我们描述了 Bcs1 功能中位于膜间空间的 N 端短片段的重要性。在酵母 Bcs1 的 N 端 44 个氨基酸残基中，前 37 个残基是可有可无的，而残基 38 中的一个疏水性氨基酸对于从线粒体基质中将 Rieske 铁硫蛋白整合到早期复合物 III 中是必需的。用亲水性氨基酸残基取代残基 38 会影响 Bcs1 的构象和与其他蛋白质的相互作用。Bcs1 在膜间空间中的保守的短 α 螺旋对于伴侣蛋白功能是一个必需的要素。
Zotero 插件