Plays Diverse Roles in DNA Damage Response, Fungal Development, and Pathogenesis in the Plant Pathogenic Fungus .

Arsenite-resistance protein 2 (Ars2) is an important nuclear protein involved in various RNA metabolisms in animals and plants, but no Ars2 ortholog has been studied in filamentous fungi. Although it is an essential gene in most model eukaryotes, null mutants were viable in the plant pathogenic fungus . The deletion of resulted in pleiotropic defects in various fungal developmental processes. mutants were irregular in nuclear division, and conidial germination was significantly retarded, causing the fungus to manifest its hypersensitive phenotypes under DNA damage stress. While deletion caused abnormal morphologies of ascospores and defective ascospore discharge, our data revealed that was not closely involved in small-non-coding RNA production in . The dominant nuclear localization of Ars2-green fluorescent proteins (GFP) and abnormal nuclear division in deletion mutant implicated that Ars2 functions in the nucleus. Intriguingly, we found that Ars2 established a robust physical interaction with the cap binding complex (CBC) to form a tertiary complex CBC-Ars2 (CBCA), and disruption of any CBCA complex subunit drastically attenuated the virulence of . The results of the study indicate that Ars2 regulates fungal development, stress response, and pathogenesis via interaction with CBC in and provide a novel insight into understanding of the biological functions of Ars2 in filamentous fungi.