Crystallographic studies on snRNP-and SMN-Associated DExD/H-box proteins and on the editosome-specific nuclease TbMP42

snRNP 和 SMN 相关 DExD/H-box 蛋白以及编辑体特异性核酸酶 TbMP42 的晶体学研究

• 批准号: 5423728
• 负责人: Professor Dr. Ralf Ficner
• 金额: --
• 依托单位: Abteilung für Molekulare Strukturbiologie
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2004
• 资助国家: 德国
• 起止时间: 2003-12-31 至 2006-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5423728?language=en
• 关键词: Crystallographic; studies; snRNP; SMN; Associated

The determination of the three-dimensional structures of protein-RNA complexes involved in mRNA maturation is a prerequiste for an understanding of their molecular function. We propose crystallographic studies on several DExD/H box proteins associated with snRNP or SMN particles as well as on a nuclease of the editosome from T. brucei. The DExD/H box proteins belong to the family of ATP-dependent helicases and exhibit an NTPase activity stimulated by dsRNA. Only a few DExD/H proteins have actually been show n to unwind dsRNA, and their activity and/or specificity might dependent on other proteins. Besides the conserved helicase domain, many DExD/H proteins contain additional domains, which are important for the interaction with other proteins and might affect the specificity and catalytic activity. Some DExD/H proteins can also disrupt protein-RNA complexes or affect the folding of RNA. At least eight DExD/H box proteins are required for the splicing of pre-mRNAs. We will focus on the crystal structure analysi s of the snRNP-associated DExD/H box proteins U5-100K (Prp28p), Prp22p and UAP56 (Sub2p), all required for pre-mRNA splicing, and of the DExD/H protein Gemin3 (Dp103), which is part of the SMN-complex involved in snRNP biogenesis. We will also determine the crystal structure of the novel nuclease TbMP42, which is involved in mRNA editing. All these crystallographic studies will preferably address the structures of functional protein-RNA or protein-protein complexes. The projects are carried out in collabora tion with the groups of Lührmann, Fischer and Göringer.

确定mRNA成熟过程中蛋白质-RNA复合物的三维结构是理解其分子功能的前提。我们建议对与snRNP或SMN颗粒相关的几种DExD/H盒蛋白以及T.布鲁塞。DExD/H盒蛋白属于ATP依赖性解旋酶家族，并表现出由dsRNA刺激的NTR活性。只有少数DExD/H蛋白实际上被证明解链dsRNA，并且它们的活性和/或特异性可能依赖于其他蛋白。除保守的解旋酶结构域外，许多DExD/H蛋白还含有其他结构域，这些结构域对与其他蛋白的相互作用非常重要，并可能影响其特异性和催化活性。一些DExD/H蛋白也可以破坏蛋白质-RNA复合物或影响RNA的折叠。前体mRNA的剪接需要至少八种DExD/H盒蛋白。我们将重点分析snRNP相关的DExD/H盒蛋白U 5 - 100 K（Prp 28 p），Prp 22 p和UAP 56（Sub 2 p）的晶体结构，所有这些蛋白都是前mRNA剪接所必需的，以及DExD/H蛋白Gemin 3（Dp 103）的晶体结构，Gemin 3是参与snRNP生物发生的SMN复合物的一部分。我们还将确定新型核酸酶TbMP 42的晶体结构，该核酸酶参与mRNA编辑。所有这些晶体学研究将优先解决功能性蛋白质-RNA或蛋白质-蛋白质复合物的结构。这些项目是与Lührmann、Fischer和Göringer的团队合作进行的。