Luna Rosa, Jimeno Sonia, Marín Mercedes, Huertas Pablo, García-Rubio María, Aguilera Andrés
Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Spain.
Mol Cell. 2005 Jun 10;18(6):711-22. doi: 10.1016/j.molcel.2005.05.001.
The conserved eukaryotic THO-TREX complex acts at the interface between transcription and mRNA export and affects transcription-associated recombination. To investigate the interdependence of nuclear mRNA processes and their impact on genomic integrity, we analyzed transcript accumulation and recombination of 40 selected mutants covering representative steps of the biogenesis and export of the messenger ribonucleoprotein particle (mRNP). None of the mutants analyzed shared the strong transcript-accumulation defect and hyperrecombination of THO mutants. Nevertheless, mutants in 3' end cleavage/polyadenylation, nuclear exosome, and mRNA export showed a weak but significant effect on recombination and transcript accumulation. Mutants of the nuclear exosome (rrp6) and 3' end processing factors (rna14 and rna15) showed inefficient transcription elongation and genetic interactions with THO. The results suggest a tight interdependence among mRNP biogenesis steps and transcription and an unexpected effect of the nuclear exosome and the cleavage/polyadenylation factors on transcription elongation and genetic integrity.
保守的真核生物THO-TREX复合物在转录和mRNA输出之间发挥作用，并影响转录相关的重组。为了研究核mRNA过程的相互依赖性及其对基因组完整性的影响，我们分析了40个选定突变体的转录本积累和重组情况，这些突变体涵盖了信使核糖核蛋白颗粒（mRNP）生物合成和输出的代表性步骤。所分析的突变体均未表现出THO突变体那样强烈的转录本积累缺陷和高重组率。然而，3'端切割/聚腺苷酸化、核外泌体和mRNA输出方面的突变体对重组和转录本积累表现出微弱但显著的影响。核外泌体（rrp6）和3'端加工因子（rna14和rna15）的突变体表现出转录延伸效率低下，并与THO存在遗传相互作用。结果表明，mRNP生物合成步骤、转录之间存在紧密的相互依赖性，并且核外泌体以及切割/聚腺苷酸化因子对转录延伸和遗传完整性具有意想不到的影响。
