title: StRas2 regulates morphogenesis, conidiation and appressorium development in Setosphaeria turcica.
abstract: The proteins of Ras family are a large group of monomeric GTPases and act as molecular switches transducing extracellular signals into the cell in higher eukaryotes. However, little is known about roles of Ras family in the foliar pathogens. In this research, we cloned the gene named StRas2 encoding Ras in Setosphaeria turcica and investigated its function by RNA interference technology. We found that the growth rate of RNAi transformants named as R1, R2, R3, R4, R5 and R6, in which the StRas2 silencing efficiency fell in turn. With the highest silencing efficiency, the transformant R1 showed anomalistic hyphae morphology, indicating its growth was significantly affected. The transformants with a middle-silencing efficiency, such as R3, R4, displayed a delay when forming appressoria and invasive hyphae. R1 could not form conidia and appressoria. However, the conidial formation in R5 and R6 was significantly reduced, and these two transformants could form appressoria and penetrate the artificial cellophane, only that its invasive hyphae were fascicular and rarely branched. The HT-toxin biological activity of all transformants showed no difference. All results suggested that StRas2 is involved in the morphogenesis, conidiation, and appressorium development and is not related to the biosynthesis of HT-toxin.
authors.affiliation: Mycotoxins and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding, China.
authors.forename: Shao-Ru
authors.initials: SR
authors.lastname: Zhang
authors.forename: Zhi-Min
authors.initials: ZM
authors.lastname: Hao
authors.forename: Li-Hui
authors.initials: LH
authors.lastname: Wang
authors.forename: Shen
authors.initials: S
authors.lastname: Shen
authors.forename: Zhi-Yan
authors.initials: ZY
authors.lastname: Cao
authors.forename: Yuan-Yuan
authors.initials: YY
authors.lastname: Xin
authors.forename: Mei-Ling
authors.initials: ML
authors.lastname: Hou
authors.forename: Shou-Qin
authors.initials: SQ
authors.lastname: Gu
authors.forename: Jian-Min
authors.initials: JM
authors.lastname: Han
authors.forename: Jin-Gao
authors.initials: JG
authors.lastname: Dong
mesh_terms: D001203:Ascomycota / Q000166:cytology* / Q000235:genetics / Q000254:growth & development*; D003001:Cloning, Molecular; D015966:Gene Expression Regulation, Fungal; D020868:Gene Silencing; D025301:Hyphae / Q000166:cytology / Q000254:growth & development; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D013172:Spores, Fungal / Q000166:cytology* / Q000254:growth & development*
chemical_list: D020559:Monomeric GTP-Binding Proteins