Native mitochondrial RNA-binding complexes in kinetoplastid RNA editing differ in guide RNA composition.
Native mitochondrial RNA-binding complexes in kinetoplastid RNA editing differ in guide RNA composition.
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DOI：
10.1261/rna.044495.114
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发表时间：
2014-07
期刊：
影响因子：
--
通讯作者：
Cruz-Reyes J
中科院分区：
文献类型：
--
作者：
Madina BR;Kumar V;Metz R;Mooers BH;Bundschuh R;Cruz-Reyes J
锥虫中的许多线粒体mRNA经历广泛的RNA编辑，包括插入和缺失尿苷残基的嵌段。本文研究了被称为线粒体RNA结合复合物或MRB的不同蛋白质复合物的RNA成分。证据支持存在含有不同RNA/蛋白质复合物的MRB的多个子复合物。动质体中的线粒体mRNA需要大量的U插入/缺失编辑，这些编辑以小块的形式从3′到5′进行，每个小块由一个向导RNA（gRNA）指导，并通过未解决的机制表现出底物和发育阶段特异性。在这里，我们解决了组成相关的因素，统称为线粒体RNA结合复合物1（MRB 1）或gRNA结合复合物（GRBC），含有gRNA，具有动态蛋白质组成，并瞬时与几个线粒体因子，包括RNA编辑核心复合物（RECC）和核糖体。MRB 1通过仍然未知的机制控制编辑。我们对MRB 1的天然亚复合物进行了第一次下一代测序研究，该亚复合物通过RNA解旋酶2（REH 2）或MRB 3010进行免疫选择，RNA解旋酶2（REH 2）结合RNA并与解旋活性相关，MRB 3010影响早期编辑步骤。这些颗粒含有REH 2或MRB 3010，但共享核心GAP 1和通过RNA光交联检测到的其他蛋白质。第一编辑区块的分析表明在MRB 3010纯化的复合物中富集了几种起始gRNA。我们的数据还表明，mRNA 3′端的快速进化和3′ UTR或C端蛋白编码序列内的菌株特异性替代3′编辑可能影响线粒体生理学。此外，我们发现编辑和预编辑的mRNA的稳健的特异性共纯化，表明这些颗粒可以结合mRNA和gRNA编辑底物。我们建议，多个亚复合物的MRB 1与不同的RNA/蛋白质组成作为一个支架的特定组装的编辑底物和RECC，从而形成编辑全酶。MRB 3010亚复合物可能通过优先招募起始gRNA来促进早期编辑。
Many mitochondrial mRNAs in trypanosomes are subject to extensive RNA editing involving both insertion and deletion of blocks of uridine residues. This paper examines the RNA constituents of distinct protein complexes known as mitochondrial RNA-binding complexes or MRBs. The evidence supports the existence of multiple subcomplexes of MRBs containing different RNA/protein composites. Mitochondrial mRNAs in kinetoplastids require extensive U-insertion/deletion editing that progresses 3′-to-5′ in small blocks, each directed by a guide RNA (gRNA), and exhibits substrate and developmental stage-specificity by unsolved mechanisms. Here, we address compositionally related factors, collectively known as the mitochondrial RNA-binding complex 1 (MRB1) or gRNA-binding complex (GRBC), that contain gRNA, have a dynamic protein composition, and transiently associate with several mitochondrial factors including RNA editing core complexes (RECC) and ribosomes. MRB1 controls editing by still unknown mechanisms. We performed the first next-generation sequencing study of native subcomplexes of MRB1, immunoselected via either RNA helicase 2 (REH2), that binds RNA and associates with unwinding activity, or MRB3010, that affects an early editing step. The particles contain either REH2 or MRB3010 but share the core GAP1 and other proteins detected by RNA photo-crosslinking. Analyses of the first editing blocks indicate an enrichment of several initiating gRNAs in the MRB3010-purified complex. Our data also indicate fast evolution of mRNA 3′ ends and strain-specific alternative 3′ editing within 3′ UTR or C-terminal protein-coding sequence that could impact mitochondrial physiology. Moreover, we found robust specific copurification of edited and pre-edited mRNAs, suggesting that these particles may bind both mRNA and gRNA editing substrates. We propose that multiple subcomplexes of MRB1 with different RNA/protein composition serve as a scaffold for specific assembly of editing substrates and RECC, thereby forming the editing holoenzyme. The MRB3010-subcomplex may promote early editing through its preferential recruitment of initiating gRNAs.
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影响因子：
4.5
作者：
Ammerman, Michelle L.;Presnyak, Vladimir;Read, Laurie K.
通讯作者：
Read, Laurie K.
影响因子：
4.5
作者：
Hashimi, Hassan;Cicova, Zdenka;Lukes, Julius
通讯作者：
Lukes, Julius
DOI：
10.1073/pnas.1014152108
发表时间：
2011-03-01
影响因子：
11.1
作者：
Li, Feng;Herrera, Jeremy;Simpson, Larry
通讯作者：
Simpson, Larry
影响因子：
5.3
作者：
Panigrahi, AK;Schnaufer, A;Stuart, KD
通讯作者：
Stuart, KD
影响因子：
14.9
作者：
Koslowsky D;Sun Y;Hindenach J;Theisen T;Lucas J
通讯作者：
Lucas J