Son Moonil, Lee Yoonseung, Kim Kook-Hyung
Department of Agricultural Biotechnology and Center for Fungal Pathogenesis, College of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea; Research Institute of Agriculture and Life Sciences, College of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea.
Department of Applied Biology and Chemistry, College of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea.
Plant Pathol J. 2016 Aug;32(4):281-9. doi: 10.5423/PPJ.OA.12.2015.0267. Epub 2016 Aug 1.
The transcription cofactor Swi6 plays important roles in regulating vegetative growth and meiosis in Saccharomyces cerevisiae. Functions of Swi6 ortholog were also characterized in Fusarium graminearum which is one of the devastating plant pathogenic fungi. Here, we report possible role of FgSwi6 in the interaction between F. graminearum and Fusarium graminearum virus 1 (FgV1) strain DK21. FgV1 perturbs biological characteristics of host fungi such as vegetative growth, sporulation, pigmentation, and reduction of the virulence (hypovirulence) of its fungal host. To characterize function(s) of FgSWI6 gene during FgV1 infection, targeted deletion, over-expression, and complementation mutants were generated and further infected successfully with FgV1. Deletion of FgSwi6 led to severe reduction of vegetative growth even aerial mycelia while over-expression did not affect any remarkable alteration of phenotype in virus-free isolates. Virus-infected (VI) FgSWI6 deletion isolate exhibited completely delayed vegetative growth. However, VI FgSWI6 over-expression mutant grew faster than any other VI isolates. To verify whether these different growth patterns in VI isolates, viral RNA quantification was carried out using qRT-PCR. Surprisingly, viral RNA accumulations in VI isolates were similar regardless of introduced mutations. These results provide evidence that FgSWI6 might play important role(s) in FgV1 induced phenotype alteration such as delayed vegetative growth.
转录辅因子Swi6在调控酿酒酵母的营养生长和减数分裂中发挥重要作用。Swi6直系同源物的功能也在禾谷镰刀菌（一种极具破坏性的植物病原真菌）中得到了表征。在此，我们报道了FgSwi6在禾谷镰刀菌与禾谷镰刀菌病毒1（FgV1）菌株DK21相互作用中的可能作用。FgV1扰乱宿主真菌的生物学特性，如营养生长、孢子形成、色素沉着，以及降低其真菌宿主的毒力（低毒力）。为了表征FgSWI6基因在FgV1感染过程中的功能，构建了靶向缺失、过表达和互补突变体，并进一步成功地用FgV1进行了感染。缺失FgSwi6导致营养生长严重减少，甚至气生菌丝也减少，而过表达在无病毒分离株中并未影响任何显著的表型改变。病毒感染（VI）的FgSWI6缺失分离株表现出完全延迟的营养生长。然而，VI FgSWI6过表达突变体比任何其他VI分离株生长得更快。为了验证VI分离株中这些不同的生长模式，使用qRT-PCR进行了病毒RNA定量。令人惊讶的是，无论引入何种突变，VI分离株中的病毒RNA积累量都相似。这些结果提供了证据，表明FgSWI6可能在FgV1诱导的表型改变（如延迟的营养生长）中发挥重要作用。
