线粒体蛋白质组研究的进展

应用蛋白质组技术已对正常人胎盘和大鼠肝线粒体蛋白质进行分离与鉴定,补充了线粒体蛋白质组数据库,并且通过比较蛋白质组学研究技术寻找病理条件下线粒体差异表达的蛋白质,为疾病的诊断和治疗提供作用靶标。随着蛋白质组技术的发展和完善,一些新方法也被应用于线粒体蛋白质的研究,推动了线粒体研究的发展。线粒体蛋白质组研究虽然已取得了一些成果,但线粒体蛋白质组数据库中的数据仍较匮乏,并且还有一些问题亟待解决和改善。     

蛋白质跨线粒体膜的运送

线粒体约含１０００种左右蛋白质,其中９８％以上系由细胞核编码,在细胞质核酸体上以前体形式合成之后再运至线粒体并选分定位于各部分,现对定位于基持和内膜的蛋白质的运送途径研究的新进展作一扼要介绍,脱血红素细胞色素ｃ是细胞色素ｃ的前体,它既不含导肽,在线粒体外膜迄今也未发现共受体,对其转运的研究概况也作了评述。     

线粒体转运蛋白质家族

线粒体转运蛋白质家族（mitochondrial transporter family）等可溶性物质载体（solute carrier,SLC）,主要包括SLC25,广泛存在于真核生物线粒体中,负责可溶性物质跨线粒体内膜的转运。SLC25家族成员拥有相似的结构特征、种类繁多的转运底物,并与细胞的多种生理功能密切相关。有研究表明,SLC25家族蛋白质的缺失或突变可导致多种代谢性疾病或神经系统疾病的发生。     

蛋白质量控制研究

细胞内蛋白的质量控制包括新翻译蛋白的正确折叠组装以及错误折叠蛋白的降解。生物体内精确的蛋白质量控制机制维持着细胞的正常生理功能,蛋白质量控制异常通常与肿瘤、衰老等多种退行性疾病的发生有关。该文对胞质、内质网以及线粒体内的蛋白质量控制机制进行了综述,旨在为全面了解蛋白质量控制异常相关疾病的发生提供参考。     

激素型肾阳虚动物肝线粒体蛋白质组与能量代谢相关性

应用凝胶内差异显示电泳技术研究肾阳虚大鼠肝线粒体蛋白质组,并从肝线粒体蛋白质组角度阐述肾阳虚与能量代谢的关系.8个分别来自于肾阳虚大鼠和正常大鼠的肝线粒体蛋白质样品(各4个)分别用荧光染料Cy3、Cy5标记,以及8个样品等量混合物用Cy2标记作为内标,每一Cy3、Cy5标记样品与Cy2标记的内标等量混合后在同一胶中进行电泳分离,经不同光激发后扫描得到不同样品的蛋白质组图谱.经DeCyder软件结合内标分析,以肾阳虚组动物与正常组动物肝线粒体蛋白质相差1.2倍以上的蛋白作为差异蛋白,实验共获得16个差异蛋白质,经质谱测定和与蛋白质文库比对,鉴定11个蛋白质.其中,肾阳虚动物热休克蛋白60和70、肌氨酸脱氢酶、氨甲酰磷酸合成酶、亚硫酸盐氧化酶、ATP合酶、醛脱氢酶和NADH脱氢酶表达量增加,而丙酮酸脱氢酶、α酮戊二酸脱氢酶、脂酰辅酶A脱氢酶和鸟氨酸氨基转移酶表达量降低.实验表明,肾阳虚动物能量代谢相关酶的变化与肾阳虚的临床虚寒症状有关.     

线粒体腺苷酸转运蛋白

腺苷酸转运蛋白(ANT)是32kDa的线粒体内膜蛋白。ANT有双重功能,一方面它能作为一个反向转运载体介导胞浆ADP和线粒体ATP的交换,另一方面,ANT能参与线粒体非特异性PTP的形成而调控细胞凋亡。现就ANT的结构、特性、功能以及ANT活性对细胞凋亡的调控进行综述。     

线粒体蛋白质表达谱的研究进展

线粒体作为细胞的一种重要细胞器, 在许多生理病理过程中发挥重要作用, 表达谱为在蛋白水平上研究线粒体功能提供新的平台。文章就线粒体表达谱的研究现状、常用的技术策略、存在的问题及发展前景做一简要综述。     

玉米T型细胞质雄性不育系与相应保持系线粒体蛋白质组中的差异蛋白

利用固相pH3—10梯度双向凝胶电泳．对玉米T型细胞质雄性不育系（T—CMS）及其相应保持系叶片（苗期、拔节期、孕穗期）,胚轴,胚根和花药（花粉母细胞减数分裂期、花粉粒小孢子单-双核期）线粒体蛋白质组中的差异蛋白进行分析。PDQuest2D图像软件分析表明,苗期和拔节期叶片约有150个蛋白质斑点,胚轴和胚根中可识别出150个线粒体蛋白质斑点,花药中约有100个斑点。利用MALDI—TOF—MS方法．运用MASCOT软件于NCBI进行数据查询．对T—CMS与相应保持系中存在的差异蛋白进行归属鉴定,在T—CMS中存在,保持系中缺失的线粒体蛋白质有：r40cl protein（胚轴中）,mature anther—specific protein,DNA—directed RNA polymerase 23kD subunit．hexokinaseⅡ和T—CMS中缺失而在保持系中存在的有：glutathione S—transferase．putative protein。其中T—CMS与相应保持系间．线粒体蛋白质组呈现出差异的组织有胚轴、胚根和小孢子单-双核期的花药。叶片的不同发育时期线粒体蛋白质组呈现明显变化．但T—CMS与保持系间没有差异。在小孢子单-双核期（花粉败育期）的花药中,T—CMS与保持系间线粒体蛋白质组出现明显差异,线粒体蛋白质组出现变异的时期与花粉败育时期相一致。     

植物核编码线粒体蛋白转动的研究进展

植物核编码蛋白向线粒体内的转运对于线粒体正常功能的发挥有着不可忽视的作用。目前在诸如前序列、前体蛋白加工、分子伴侣及线粒体与质体（或叶绿体）之间分选等几方面开展了许多研究。本综述以上方面的研究进展。     

Molecular Chaperones and Mitochondrial Protein Folding

Precursor proteins destined for the mitochondrial matrix traverse inner and outer organelle membranes in an extended conformation. Translocation events are therefore integrally coupled to the processes of protein unfolding in the cytosol and protein refolding in the matrix. To successfully import proteins from the cytoplasm into mitochondria, cells have recruited a variety of molecular chaperone systems and folding catalysts. Within the organelles, mitochondrial Hsp70 (mt-Hsp70) is a major player in this process and exerts multiple functions. First, mt-Hsp70 binds together with cohort proteins to incoming polypeptide chains, thus conferring unidirectionality on the translocation process, and then assists in their refolding. A subset of imported proteins requires additional assistance by chaperonins of the Hsp60/Hsp10 family. Protein folding occurs within the cavity of these cylindrical complexes. A productive interaction of precursor proteins with molecular chaperones in the matrix is not only crucial for correct refolding and assembly, but also for processing of presequences, intramitochondrial sorting, and degradation of proteins. This review focuses on the role of mt-Hsp70 and Hsp60/Hsp10 in protein folding in the mitochondrial matrix and discusses recent findings on their molecular mechanism of action.     

Mitochondrial biology and dysfunction in secondary mitochondrial disease

Mitochondrial diseases are a broad, genetically heterogeneous class of metabolic disorders characterized by deficits in oxidative phosphorylation (OXPHOS). Primary mitochondrial disease (PMD) defines pathologies resulting from mutation of mitochondrial DNA (mtDNA) or nuclear genes affecting either mtDNA expression or the biogenesis and function of the respiratory chain. Secondary mitochondrial disease (SMD) arises due to mutation of nuclear-encoded genes independent of, or indirectly influencing OXPHOS assembly and operation. Despite instances of novel SMD increasing year-on-year, PMD is much more widely discussed in the literature. Indeed, since the implementation of next generation sequencing (NGS) techniques in 2010, many novel mitochondrial disease genes have been identified, approximately half of which are linked to SMD. This review will consolidate existing knowledge of SMDs and outline discrete categories within which to better understand the diversity of SMD phenotypes. By providing context to the biochemical and molecular pathways perturbed in SMD, we hope to further demonstrate the intricacies of SMD pathologies outside of their indirect contribution to mitochondrial energy generation.     

The Diverged Trypanosome MICOS Complex as a Hub for Mitochondrial Cristae Shaping and Protein Import

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膜蛋白ATAD3A在线粒体质量控制中的作用

线粒体质量控制对于线粒体网络的稳态和线粒体功能的正常发挥具有重要意义。三磷酸腺苷酶家族蛋白3A(ATAD3A)是同时参与调节线粒体结构功能、线粒体动力学和线粒体自噬等重要生物学过程的线粒体膜蛋白之一。近期研究表明,ATAD3A既可与Mic60/Mitofilin和线粒体转录因子A (TFAM)等因子相互作用以维持线粒体嵴的形态和氧化磷酸化功能,又能与发动蛋白相关蛋白1 (Drp1)结合而正性/负性调节线粒体分裂,还可作为线粒体外膜转位酶（TOM）复合物和线粒体内膜转位酶（TIM）复合物之间的桥接因子而介导PTEN诱导激酶（PINK1）输入线粒体进行加工,显示出促自噬或抗自噬活性。本文对ATAD3A在调控线粒体质量控制中的作用及其机制进行了综述。     

The MitoLuc Assay System for Accurate Real-Time Monitoring of Mitochondrial Protein Import Within Mammalian Cells

Mitochondrial protein import is critical for organelle biogenesis, bioenergetic function, and health. The mechanism of which is poorly understood, particularly of the mammalian system. To address this problem we have established an assay to quantitatively monitor mitochondrial import inside mammalian cells. The reporter is based on a split luciferase, whereby the large fragment is segregated in the mitochondrial matrix and the small complementary fragment is fused to the C-terminus of a purified recombinant precursor protein destined for import. Following import the complementary fragments combine to form an active luciferase–providing a sensitive, accurate and continuous measure of protein import. This advance allows detailed mechanistic examination of the transport process in live cells, including the analysis of import breakdown associated with disease, and high-throughput drug screening. Furthermore, the set-up has the potential to be adapted for the analysis of alternative protein transport systems within different cell types, and multicellular model organisms.     

Pre-emptive Quality Control of a Misfolded Membrane Protein by Ribosome-Driven Effects

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人类蛋白质组表达谱蛋白质鉴定的分步搜索策略

大规模蛋白质组表达谱研究的蛋白质鉴定一般采取基于数据库搜索的策略,因此数据库的选择及搜索策略在蛋白质鉴定中非常重要。现有的人类蛋白质数据库远不够完善,而从其他物种的蛋白质数据库中所能得到的补充非常有限,但人类基因组数据库中却可能含有很大的补充空间。在对国际人类蛋白质数据库充分调研、比较的基础上,提出了一种分步搜索的策略。这种策略首先利用一个质量较高、覆盖率相对较大的非冗余数据库进行基本鉴定,随后利用其他蛋白和核酸数据库进行补充鉴定和新蛋白挖掘。该策略能有效地鉴定尽可能多的高可靠蛋白,并能进一步充分利用质谱数据进行补充鉴定和新蛋白挖掘,对大规模蛋白质组表达谱研究具有重要的意义。     

Porin Associates with Tom22 to Regulate the Mitochondrial Protein Gate Assembly

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Proteome Imbalance of Mitochondrial Electron Transport Chain in Brown Adipocytes Leads to Metabolic Benefits

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