Evidence that Dim1 associates with proteins involved in pre-mRNA splicing, and delineation of residues essential for Dim1 interactions with hnRNP F and Npw38/PQBP-1
Evidence that Dim1 associates with proteins involved in pre-mRNA splicing, and delineation of residues essential for Dim1 interactions with hnRNP F and Npw38/PQBP-1
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DOI：
10.1016/s0378-1119(00)00372-3
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发表时间：
2000-10-17
期刊：
影响因子：
3.5
通讯作者：
Golemis, EA
中科院分区：
文献类型：
--
作者：
Zhang, YZ;Lindblom, T;Golemis, EA
小的进化保守的蛋白质Dim 1 p/hDim 1/Dib 1 p/DML-1最初被定义为通过G2/M转换的进展所必需的因子，并显示需要维持分裂酵母后期促进复合物/环体的组分的稳态水平。最近，Dib 1 p被定义为U4/U6的一个组件。U 5 tri-snRNP，前体mRNA剪接所需。为了研究Dim 1功能的机制，进行迭代双杂交筛选以鉴定相互作用蛋白。由此鉴定的蛋白质仅是那些参与前mRNA剪接或相关功能的蛋白质，并且当与hDim 1在哺乳动物细胞中共表达时，一个伴侣诱导了引人注目的合成表型。饱和丙氨酸扫描诱变的Dim 1允许描绘的氨基酸的能力，其相互作用的定义的合作伙伴：映射这些残基的hDim 1的结构坐标定义的蛋白质的相互作用的部门。最后，最近的耗竭研究表明，Dim 1的功能是必不可少的前mRNA剪接在酵母中。我们发现C. RNA干扰导致原肠形成过程中胚胎死亡，其标志是不能正确表达早期合子转录本。这些结果与合子基因表达的全局破坏相关的逮捕表型平行，表明Dim 1蛋白在高等真核生物的基因表达中保持着重要的功能。(C)2000 Elsevier Science B. V.保留所有权利。
The small evolutionarily conserved protein Dim1p/hDim1/Dib1p/DML-1 was initially defined as a factor essential for progression through the G2/M transition, and shown to be required to maintain the steady state level of a component of the fission yeast anaphase promoting complex/cyclosome. More recently, Dib1p has been defined as a component of the U4/U6 . U5 tri-snRNP, required for pre-mRNA splicing. To investigate the mechanism(s) of Dim1 function, reiterative two-hybrid screening was performed to identify interacting proteins. Proteins thus identified were solely those involved in pre-mRNA splicing or related functions, and one partner induced a striking synthetic phenotype when co-expressed with hDim1 in mammalian cells. Saturating alanine scanning mutagenesis of Dim1 allowed delineation of amino acids essential for its ability to interact with its defined partners: mapping these residues on the structural coordinates of hDim1 defined an interactive sector of the protein. Finally, depletion studies have recently shown that Dim1 function is essential for pre-mRNA splicing in yeast. We find that elimination of DML-1 expression in C. elegans by RNA interference leads to embryonal lethality during gastrulation, marked by a failure to correctly express early zygotic transcripts. These results parallel the arrest phenotypes associated with global disruption of zygotic gene expression, suggesting that Dim1 proteins maintain an essential function in gene expression in higher eukaryotes. (C) 2000 Elsevier Science B.V. All rights reserved.