Zhang Yimei, Dai Yafeng, Huang Yi, Wang Kai, Lu Ping, Xu Hanfang, Xu Jin-Rong, Liu Huiquan
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, 712100, Shaanxi, China.
College of Life Science, Xinyang Normal University, Xinyang, 464000, China.
Curr Genet. 2020 Jun;66(3):607-619. doi: 10.1007/s00294-020-01054-2. Epub 2020 Feb 10.
Serine/arginine (SR) proteins play significant roles in pre-mRNA splicing in eukaryotes. To investigate how gene expression influences fungal development and pathogenicity in Fusarium graminearum, a causal agent of Fusarium head blight (FHB) of wheat and barley, our previous study identified a SR protein FgSrp1 in F. graminearum, and showed that it is important for conidiation, plant infection and pre-mRNA processing. In this study, we identified another SR protein FgSrp2 in F. graminearum, which is orthologous to Schizosaccharomyces pombe Srp2. Our data showed that, whereas yeast Srp2 is essential for growth, deletion of FgSRP2 resulted in only slight defects in vegetative growth and perithecia melanization. FgSrp2 localized to the nucleus and both its N- and C-terminal regions were important for the localization to the nucleus. FgSrp2 interacted with FgSrp1 to form a complex in vivo. Double deletion of FgSRP1 and FgSRP2 revealed that they had overlapping functions in vegetative growth and sexual reproduction. RNA-seq analysis revealed that, although deletion of FgSRP2 alone had minimal effects, deletion of both FgSRP1 and FgSRP2 caused significant changes in gene transcription and RNA splicing. Overall, our results indicated that FgSrp2 regulates vegetative growth, sexual reproduction and pre-mRNA processing by interacting with FgSrp1.
丝氨酸/精氨酸（SR）蛋白在真核生物的前体mRNA剪接中发挥着重要作用。为了研究基因表达如何影响禾谷镰刀菌（小麦和大麦赤霉病的病原体）的真菌发育和致病性，我们之前的研究在禾谷镰刀菌中鉴定出一种SR蛋白FgSrp1，并表明它对分生孢子形成、植物感染和前体mRNA加工很重要。在本研究中，我们在禾谷镰刀菌中鉴定出另一种SR蛋白FgSrp2，它与粟酒裂殖酵母的Srp2直系同源。我们的数据表明，虽然酵母Srp2对生长至关重要，但FgSRP2的缺失仅导致营养生长和子囊壳黑化方面的轻微缺陷。FgSrp2定位于细胞核，其N端和C端区域对细胞核定位都很重要。FgSrp2在体内与FgSrp1相互作用形成复合物。FgSRP1和FgSRP2的双缺失表明它们在营养生长和有性生殖中具有重叠功能。RNA测序分析表明，虽然单独缺失FgSRP2影响最小，但同时缺失FgSRP1和FgSRP2会导致基因转录和RNA剪接发生显著变化。总体而言，我们的结果表明FgSrp2通过与FgSrp1相互作用来调节营养生长、有性生殖和前体mRNA加工。
