Grimm Thomas, Hölzel Michael, Rohrmoser Michaela, Harasim Thomas, Malamoussi Anastassia, Gruber-Eber Anita, Kremmer Elisabeth, Eick Dirk
Institute of Clinical Molecular Biology and Tumour Genetics, GSF Research Centre for Environment and Health, Marchioninistrasse 25, 81377 Munich, Germany.
Nucleic Acids Res. 2006 May 31;34(10):3030-43. doi: 10.1093/nar/gkl378. Print 2006.
The nucleolar PeBoW-complex, consisting of Pes1, Bop1 and WDR12, is essential for cell proliferation and processing of ribosomal RNA in mammalian cells. Here we have analysed the physical and functional interactions of Pes1 deletion mutants with the PeBoW-complex. Pes1 mutants M1 and M5, with N- and C-terminal truncations, respectively, displayed a dominant-negative phenotype. Both mutants showed nucleolar localization, blocked processing of the 36S/32S precursors to mature 28S rRNA, inhibited cell proliferation, and induced high p53 levels in proliferating, but not in resting cells. Mutant M1 and M5 proteins associated with large pre-ribosomal complexes and co-immunoprecipitated Bop1 and WDR12 proteins indicating their proper incorporation into the PeBoW-complex. We conclude that the dominant-negative effect of the M1 and M5 mutants is mediated by the impaired function of the PeBoW-complex.
由Pes1、Bop1和WDR12组成的核仁PeBoW复合物对哺乳动物细胞的增殖和核糖体RNA的加工至关重要。在此，我们分析了Pes1缺失突变体与PeBoW复合物的物理和功能相互作用。分别具有N端和C端截短的Pes1突变体M1和M5表现出显性负性表型。这两个突变体均显示核仁定位，阻断了36S/32S前体加工成成熟的28S rRNA，抑制细胞增殖，并在增殖细胞而非静止细胞中诱导高p53水平。突变体M1和M5蛋白与大型核糖体前体复合物相关，并与Bop1和WDR12蛋白进行共免疫沉淀，表明它们正确地整合到了PeBoW复合物中。我们得出结论，M1和M5突变体的显性负性效应是由PeBoW复合物功能受损介导的。
