Structural insights into RNA polymerase recognition and essential function of Myxococcus xanthus CdnL.
Structural insights into RNA polymerase recognition and essential function of Myxococcus xanthus CdnL.
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对RNA聚合酶识别的结构洞察力和粘膜CDNL的基本功能。
DOI：
10.1371/journal.pone.0108946
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发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Padmanabhan S
中科院分区：
文献类型：
--
作者：
Gallego-García A;Mirassou Y;García-Moreno D;Elías-Arnanz M;Jiménez MA;Padmanabhan S
CdnL和CarD是细菌RNA聚合酶（RNAP）相互作用蛋白质的CarD_CdnL_TRCF家族的两个功能不同的成员，其共存于黄色粘球菌中。虽然仅在粘细菌中发现的CardD与各种细胞质外功能（ECF）σ-因子的活性有关，但其同源物在细菌中广泛存在的必需CdnL的功能和作用方式仍有待于在M. xanthus在这里，我们报告的核磁共振溶液结构的CdnL，并提出了一个基于结构的突变分析其功能。双结构域CdnL中的N末端五链β折叠Tudor样模块介导与RNAP-β的结合，破坏这种相互作用的突变会损害细胞生长。CdnL的C端结构域由5个α螺旋折叠而成，并含有一片暴露于溶剂中的非极性和碱性残基，其中一组碱性残基对CdnL的功能至关重要。我们表明，CdnL，而不是其功能丧失的突变体，稳定形成的转录能力，开放的复合物的主要σA-RNAP全酶在体外的rRNA启动子。与此一致，CdnL存在于体内rRNA启动子处。CdnL在M. RNAP-σA活性和CardD在ECF-σ功能中的意义Xanthus阐明了广泛分布的细菌蛋白质家族中的两个相关成员如何进化以实现不同的σ依赖性启动子活性。
CdnL and CarD are two functionally distinct members of the CarD_CdnL_TRCF family of bacterial RNA polymerase (RNAP)-interacting proteins, which co-exist in Myxococcus xanthus. While CarD, found exclusively in myxobacteria, has been implicated in the activity of various extracytoplasmic function (ECF) σ-factors, the function and mode of action of the essential CdnL, whose homologs are widespread among bacteria, remain to be elucidated in M. xanthus. Here, we report the NMR solution structure of CdnL and present a structure-based mutational analysis of its function. An N-terminal five-stranded β-sheet Tudor-like module in the two-domain CdnL mediates binding to RNAP-β, and mutations that disrupt this interaction impair cell growth. The compact CdnL C-terminal domain consists of five α-helices folded as in some tetratricopeptide repeat-like protein-protein interaction domains, and contains a patch of solvent-exposed nonpolar and basic residues, among which a set of basic residues is shown to be crucial for CdnL function. We show that CdnL, but not its loss-of-function mutants, stabilizes formation of transcriptionally competent, open complexes by the primary σA-RNAP holoenzyme at an rRNA promoter in vitro. Consistent with this, CdnL is present at rRNA promoters in vivo. Implication of CdnL in RNAP-σA activity and of CarD in ECF-σ function in M. xanthus exemplifies how two related members within a widespread bacterial protein family have evolved to enable distinct σ-dependent promoter activity.
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影响因子：
3.2
作者：
Garcia-Heras, Francisco;Abellon-Ruiz, Javier;Elias-Arnanz, Montserrat
通讯作者：
Elias-Arnanz, Montserrat
影响因子：
3.2
作者：
Garcia-Moreno, Diana;Carmen Polanco, Maria;Elias-Arnanz, Montserrat
通讯作者：
Elias-Arnanz, Montserrat
DOI：
10.1073/pnas.1311642110
发表时间：
2013-10-01
影响因子：
11.1
作者：
Banta, Amy B.;Chumanov, Robert S.;Gourse, Richard L.
通讯作者：
Gourse, Richard L.
DOI：
10.1007/s00249-005-0473-0
发表时间：
2005-11-01
影响因子：
2
作者：
García-Mayoral, MF;Pantoja-Uceda, D;Bruix, M
通讯作者：
Bruix, M
影响因子：
5.7
作者：
Gulten, Gulcin;Sacchettini, James C.
通讯作者：
Sacchettini, James C.