Wong Koon Ho, Todd Richard B, Oakley Berl R, Oakley C Elizabeth, Hynes Michael J, Davis Meryl A
Department of Genetics, The University of Melbourne, Grattan Street, Parkville, Vic. 3010, Australia.
Fungal Genet Biol. 2008 May;45(5):728-37. doi: 10.1016/j.fgb.2007.12.009. Epub 2008 Jan 11.
Sumoylation, the reversible covalent attachment of small ubiquitin-like modifier (SUMO) peptides has emerged as an important regulator of target protein function. In Saccharomyces cerevisiae, but not in Schizosaccharyomes pombe, deletion of the gene encoding SUMO peptides is lethal. We have characterized the SUMO-encoding gene, sumO, in the filamentous fungus Aspergillus nidulans. The sumO gene was deleted in a diploid and sumODelta haploids were recovered. The mutant was viable but exhibited impaired growth, reduced conidiation and self-sterility. Overexpression of epitope-tagged SumO peptides revealed multiple sumoylation targets in A. nidulans and SumO overexpression resulted in greatly increased levels of protein sumoylation without obvious phenotypic consequences. Using five-piece fusion PCR, we generated a gfp-sumO fusion gene expressed from the sumO promoter for live-cell imaging of GFP-SumO and GFP-SumO-conjugated proteins. Localization of GFP-SumO is dynamic, accumulating in punctate spots within the nucleus during interphase, lost at the onset of mitosis and re-accumulating during telophase.
小泛素样修饰物（SUMO）肽的可逆共价连接即SUMO化，已成为靶蛋白功能的重要调节因子。在酿酒酵母中，而非在粟酒裂殖酵母中，编码SUMO肽的基因缺失是致死的。我们已对丝状真菌构巢曲霉中编码SUMO的基因sumO进行了表征。在二倍体中删除了sumO基因，并获得了sumOΔ单倍体。该突变体是存活的，但生长受损、分生孢子形成减少且自交不育。表位标记的SumO肽的过表达揭示了构巢曲霉中的多个SUMO化靶标，并且SumO过表达导致蛋白质SUMO化水平大幅增加，而没有明显的表型后果。我们使用五片段融合PCR，构建了一个由sumO启动子表达的gfp-sumO融合基因，用于对GFP-SumO和GFP-SumO缀合蛋白进行活细胞成像。GFP-SumO的定位是动态的，在间期积聚在细胞核内的点状斑点中，在有丝分裂开始时消失，并在末期重新积聚。
