Identification of human mitochondrial metabolome proteins

线粒体DNA （mtDNA）编码线粒体电子传递系统所必需的基因。最近，我们提出mtDNA具有一个称为类核的大型蛋白质- dna复合体，而类核结构对mtDNA的维持至关重要。线粒体转录因子A （TFAM）是类核的主要成分。在本研究中，我的目标是通过LC/MS/MS鉴定类核的蛋白质成分。（方法）用c交联剂处理分离的人线粒体。溶解后，用抗team抗体免疫沉淀类核。通过SDS-PAGE对沉淀蛋白进行一维分离、提取、三聚氰胺化、LC/MS/MS分析。（结果）1)潜在的DNA或RNA结合蛋白，2)热休克蛋白，3)核糖体蛋白，4)TCA循环相关蛋白，5)脂肪酸β氧化酶。这些结果表明，线粒体类核为翻译、TCA循环和脂肪酸β氧化的有效代谢提供了一个支架。

(Aim) Mitochondrial DNA (mtDNA) encodes genes essential for the mitochondrial electron transfer system. Recently we proposed that mtDNA takes on a large protein-DNA complex called nucleoid and the nucleoid structure is critical for maintenance of mtDNA. Mitochondrial transcription factor A (TFAM) is a main component of the nucleoid. In this study, I aim to identify protein components of the nucleoid by LC/MS/MS.(Methods) Isolated human mitochondria were treated with a c ross-linker. After solubilization, the nucleoid was immunoprecipitated with anti-TEAM antibody. The precipitated proteins were separated on one dimensional SDS-PAGE, extracted, tripsinized, and and analyzed by LC/MS/MS.(Results)1)Potential DNA- or RNA binding proteins2)Heat shock proteins3)Ribosomal proteins4)TCA cycle related proteins5)Enzymes for β oxidation of fatty acidsAll proteins identified were classified into only 5 groups as above. These results suggest that the mitochondrial nucleoid provides a scaffold for efficient metabolism of translation, TCA cycles, and β oxidation of fatty acids.