Locations of membrane protein production in a cyanobacterium.
Locations of membrane protein production in a cyanobacterium.
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DOI：
10.1128/jb.00209-23
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发表时间：
2023-10-26
影响因子：
3.2
通讯作者：
Mullineaux, Conrad W.
中科院分区：
文献类型：
--
作者：
Mahbub, Moontaha;Mullineaux, Conrad W.
蓝藻表现出异常复杂的原核细胞结构，包括独特的胞质内膜系统，类囊体膜是光合光反应的场所。类囊体膜和质膜具有截然不同的蛋白质组，但将蛋白质靶向特定膜的机制仍然知之甚少。在此，我们研究了模型单细胞蓝藻长聚球菌PCC 7942中类囊体蛋白和质膜蛋白的翻译位置。我们利用荧光原位杂交技术探测编码膜整合蛋白的mrna的位置，并利用绿色荧光蛋白标记RplL亚基来揭示不同条件下核糖体的位置。我们发现膜整合类囊体蛋白和质膜蛋白在不同的位置翻译。类囊体膜蛋白在面向类核的最内层类囊体膜表面成片翻译。然而，不同的蛋白质在不同的片段中被翻译，即使它们是相同多蛋白复合物的亚基。这意味着翻译分布在近端类囊体表面，新插入的蛋白质在融入复合物之前在膜内迁移。编码质膜蛋白的mrna在质膜上形成斑块。在类囊体和质膜附近的类似位置可以观察到核糖体，当条件迫使质膜蛋白快速产生时，在质膜附近可以观察到更多的核糖体。核糖体和mrna必须有途径通过类囊体到达质膜。我们推断了一个陪伴质膜mrna的系统，以防止它们在到达正确的膜之前被翻译。蓝藻在细胞质中有一个复杂而独特的膜系统，类囊体膜容纳光合作用的光反应。类囊体膜和质膜含有不同的蛋白质，但将蛋白质靶向到这两种膜的步骤尚不清楚。了解蛋白质分选规则对于蓝藻细胞的生物技术重组和理解类囊体的进化发展至关重要。在这里，我们探索编码蓝藻膜蛋白的mrna和翻译它们的核糖体的亚细胞位置。我们发现类囊体蛋白和质膜蛋白是在不同的位置产生的，这为蛋白质翻译之前的分选机制提供了第一个直接证据。
Cyanobacteria show an unusually complex prokaryotic cell structure including a distinct intracytoplasmic membrane system, the thylakoid membranes that are the site of the photosynthetic light reactions. The thylakoid and plasma membranes have sharply distinct proteomes, but the mechanisms that target proteins to a specific membrane remain poorly understood. Here, we investigate the locations of translation of thylakoid and plasma membrane proteins in the model unicellular cyanobacterium Synechococcus elongatus PCC 7942. We use fluorescent in situ hybridization to probe the locations of mRNAs encoding membrane-integral proteins, plus Green Fluorescent Protein tagging of the RplL subunit to reveal the location of ribosomes under different conditions. We show that membrane-integral thylakoid and plasma membrane proteins are translated in different locations. Thylakoid membrane proteins are translated in patches at the innermost thylakoid membrane surface facing the nucleoid. However, different proteins are translated in different patches, even when they are subunits of the same multiprotein complex. This implies that translation is distributed over the proximal thylakoid surface, with newly inserted proteins migrating within the membrane prior to incorporation into complexes. mRNAs encoding plasma membrane proteins form patches at the plasma membrane. Ribosomes can be observed at similar locations near the thylakoid and plasma membranes, with more ribosomes near the plasma membrane when conditions force rapid production of plasma membrane proteins. There must be routes for ribosomes and mRNAs past the thylakoids to the plasma membrane. We infer a system to chaperone plasma membrane mRNAs to prevent their translation prior to arrival at the correct membrane. Cyanobacteria have a complex and distinct membrane system within the cytoplasm, the thylakoid membranes that house the photosynthetic light reactions. The thylakoid and plasma membranes contain distinct sets of proteins, but the steps that target proteins to the two membranes remain unclear. Knowledge of the protein sorting rules will be crucial for the biotechnological re-engineering of cyanobacterial cells, and for understanding the evolutionary development of the thylakoids. Here, we probe the subcellular locations of the mRNAs that encode cyanobacterial membrane proteins and the ribosomes that translate them. We show that thylakoid and plasma membrane proteins are produced at different locations, providing the first direct evidence for a sorting mechanism that operates prior to protein translation.
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影响因子：
16.6
作者：
Huokko T;Ni T;Dykes GF;Simpson DM;Brownridge P;Conradi FD;Beynon RJ;Nixon PJ;Mullineaux CW;Zhang P;Liu LN
通讯作者：
Liu LN
影响因子：
4.3
作者：
Frain, Kelly M.;Gangl, Doris;Robinson, Colin
通讯作者：
Robinson, Colin
影响因子：
18
作者：
Rast, Anna;Schaffer, Miroslava;Engel, Benjamin D.
通讯作者：
Engel, Benjamin D.
DOI：
10.1093/dnares/dsu018
发表时间：
2014-10
期刊：
DNA research : an international journal for rapid publication of reports on genes and genomes
影响因子：
--
作者：
Kopf M;Klähn S;Scholz I;Matthiessen JK;Hess WR;Voß B
通讯作者：
Voß B
DOI：
10.1093/plcell/koaa017
发表时间：
2021-04-17
期刊：
The Plant cell
影响因子：
--
作者：
Riediger M;Spät P;Bilger R;Voigt K;Maček B;Hess WR
通讯作者：
Hess WR