title: StSTE12 is required for the pathogenicity of Setosphaeria turcica by regulating appressorium development and penetration.
abstract: In filamentous fungi, the pathogenic mitogen-activated protein kinase (PMK) pathway performs an important function in plant infection. STE12-like genes found in higher eukaryotes encode transcription factors and are regulated by the PMK pathway. However, the functions of STE12-like genes in foliar pathogens remain poorly understood. In this study, we cloned StSTE12 from Setosphaeria turcica and investigated its functions by RNA interference. Transformants ste12-3, ste12-2 and, ste12-1, in which the StSTE12 silencing efficiency increased in order, were confirmed by real time PCR. Compared with the wild-type (WT) strain, the transformants showed reduced growth rate, lighter colony color, and obviously decreased conidium production. More importantly, different to WT strain and ste12-3 with lower StSTE12silencing efficiency, ste12-1 and ste12-2 with higher StSTE12 silencing efficiency were nonpathogenic on intact leaves, but pathogenic on wounded leaves. However, the biological activity of HT-toxin from all transformants showed no difference on corn leaves. Furthermore, ste12-1 and ste12-2 did not penetrate artificial cellophane membrane and showed abnormal and delayed development appressoria. Although it could penetrate the cellophane membranes, ste12-3 formed appressoria after 48 h of inoculation more than WT. Therefore, StSTE12 was involved in vegetative growth, conidiation, appressorial development, penetration as well as the pathogenicity, but it was not related to HT-toxin biosynthesis. More interestingly, all the results suggested that StSTE12 was crucial for pathogenicity due to involvement in regulating appressoria development and penetration.
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China.
authors.forename: Shou-Qin
authors.initials: SQ
authors.lastname: Gu
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China; Plant Protection Institute, Hebei Academy of Agriculture and Forestry Sciences, Baoding 071001, PR China. Electronic address: lipo-0524@163.com.
authors.forename: Po
authors.initials: P
authors.lastname: Li
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China.
authors.forename: Min
authors.initials: M
authors.lastname: Wu
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China.
authors.forename: Zhi-Min
authors.initials: ZM
authors.lastname: Hao
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China.
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Gong
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China.
authors.forename: Xiao-Yu
authors.initials: XY
authors.lastname: Zhang
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China.
authors.forename: Lan
authors.initials: L
authors.lastname: Tian
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China.
authors.forename: Pan
authors.initials: P
authors.lastname: Zhang
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China.
authors.forename: Zhi-Yan
authors.initials: ZY
authors.lastname: Cao
authors.affiliation: Tangshan Normal University, Tangshan 063000, PR China.
authors.forename: Yong-Shan
authors.initials: YS
authors.lastname: Fan
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China. Electronic address: hanjmnd@163.com.
authors.forename: Jian-Min
authors.initials: JM
authors.lastname: Han
authors.affiliation: Mycotoxin and Molecular Plant Pathology Laboratory, Agricultural University of Hebei, Baoding 071001, PR China. Electronic address: dongjingao@126.com.
authors.forename: Jin-Gao
authors.initials: JG
authors.lastname: Dong
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000472:pathogenicity*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D008969:Molecular Sequence Data; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology*; D016415:Sequence Alignment; D013172:Spores, Fungal / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism / Q000472:pathogenicity; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014774:Virulence; D003313:Zea mays / Q000382:microbiology*
chemical_list: D005656:Fungal Proteins; D014157:Transcription Factors
keywords: Appressorium development; Penetration; RNA interference; Setosphaeria turcica; StSTE12