西亚试剂：Structure of a tyrosyl-tRNA synthetase splicing factor boun

发布时间：2025-06-04

Nature 451, 94-97 (3 January 2008) | doi:10.1038/nature06413; Received 26 September 2007; Accepted 24 October 2007

Structure of a tyrosyl-tRNA synthetase splicing factor bound to a group I intron RNA

Paul J. Paukstelis1, Jui-Hui Chen2, Elaine Chase2, Alan M. Lambowitz1,3 & Barbara L. Golden2,3

Correspondence to: Alan M. Lambowitz1,3Barbara L. Golden2,3 Correspondence and requests for materials should be addressed to A.M.L. (Email: lambowitz@mail.utexas.edu) or B.L.G. (Email: barbgolden@purdue.edu).

The 'RNA world' hypothesis holds that during evolution the structural and enzymatic functions initially served by RNA were assumed by proteins, leading to the latter's domination of biological catalysis. This progression can still be seen in modern biology, where ribozymes, such as the ribosome and RNase P, have evolved into protein-dependent RNA catalysts ('RNPzymes'). Similarly, group I introns use RNA-catalysed splicing reactions, but many function as RNPzymes bound to proteins that stabilize their catalytically active RNA structure1, 2. One such protein, the Neurospora crassa mitochondrial tyrosyl-tRNA synthetase (TyrRS; CYT-18), is bifunctional and both aminoacylates mitochondrial tRNATyr and promotes the splicing of mitochondrial group I introns3. Here we determine a 4.5-Å co-crystal structure of the Twort orf142-I2 group I intron ribozyme bound to splicing-active, carboxy-terminally truncated CYT-18. The structure shows that the group I intron binds across the two subunits of the homodimeric protein with a newly evolved RNA-binding surface distinct from that which binds tRNATyr. This RNA binding surface provides an extended scaffold for the phosphodiester backbone of the conserved catalytic core of the intron RNA, allowing the protein to promote the splicing of a wide variety of group I introns. The group I intron-binding surface includes three small insertions and additional structural adaptations relative to non-splicing bacterial TyrRSs, indicating a multistep adaptation for splicing function. The co-crystal structure provides insight into how CYT-18 promotes group I intron splicing, how it evolved to have this function, and how proteins could have incrementally replaced RNA structures during the transition from an RNA world to an RNP world.

• 以上资料由西亚试剂：http://www.xiyashiji.com/ 提供此产品的详细信息如密度,含量,分子式,分子量等均可在西亚官网查询   
• 相关产品如溴化汞硝酸亚汞氯化亚汞乙酸苯汞氯化钾汞 碘化汞钾硫氰酸汞硫酸亚汞氧化汞氯化汞碘化汞硝酸汞三氯氧磷三氯化磷碘甲烷二碘甲烷三碘甲烷三氟碘甲烷氘代碘甲烷碘乙烷1,2-二碘乙烷甲酸铷碘化铷溴化铷铬酸铷硫酸铷氟化铷硝酸铷氯化铷碳酸铷硫酸镱 碳酸镱氯化镱硝酸镱氧化镱等均有销售.欢迎订购

上一篇：西亚试剂：介电电泳分离的原理是细胞在高频不均匀电场作用下产生极化
下一篇：研究人员研发酒精中毒和酒精滥用的个性化疗法