title: An Atypical Thioredoxin Imparts Early Resistance to Sugarcane Mosaic Virus in Maize.
abstract: Sugarcane mosaic virus (SCMV) causes substantial losses of grain yield and forage biomass in susceptible maize worldwide. A major quantitative trait locus, Scmv1, has been identified to impart strong resistance to SCMV at the early infection stage. Here, we demonstrate that ZmTrxh, encoding an atypical h-type thioredoxin, is the causal gene at Scmv1, and that its transcript abundance correlated strongly with maize resistance to SCMV. ZmTrxh alleles, whether they are resistant or susceptible, share the identical coding/proximal promoter regions, but vary in the upstream regulatory regions. ZmTrxh lacks two canonical cysteines in the thioredoxin active-site motif and exists uniquely in the maize genome. Because of this, ZmTrxh is unable to reduce disulfide bridges but possesses a strong molecular chaperone-like activity. ZmTrxh is dispersed in maize cytoplasm to suppress SCMV viral RNA accumulation. Moreover, ZmTrxh-mediated maize resistance to SCMV showed no obvious correlation with the salicylic acid- and jasmonic acid-related defense signaling pathways. Taken together, our results indicate that ZmTrxh exhibits a distinct defense profile in maize resistance to SCMV, differing from previously characterized dominant or recessive potyvirus resistance genes.
authors.affiliation: National Maize Improvement Centre of China, China Agricultural University, Beijing 100193, China.
authors.forename: Qingqing
authors.initials: Q
authors.lastname: Liu
authors.affiliation: National Maize Improvement Centre of China, China Agricultural University, Beijing 100193, China.
authors.forename: Huanhuan
authors.initials: H
authors.lastname: Liu
authors.affiliation: National Maize Improvement Centre of China, China Agricultural University, Beijing 100193, China.
authors.forename: Yangqing
authors.initials: Y
authors.lastname: Gong
authors.affiliation: National Maize Improvement Centre of China, China Agricultural University, Beijing 100193, China.
authors.forename: Yongfu
authors.initials: Y
authors.lastname: Tao
authors.affiliation: National Maize Improvement Centre of China, China Agricultural University, Beijing 100193, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Jiang
authors.affiliation: National Maize Improvement Centre of China, China Agricultural University, Beijing 100193, China.
authors.forename: Weiliang
authors.initials: W
authors.lastname: Zuo
authors.affiliation: National Maize Improvement Centre of China, China Agricultural University, Beijing 100193, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Yang
authors.affiliation: National Maize Improvement Centre of China, China Agricultural University, Beijing 100193, China.
authors.forename: Jianrong
authors.initials: J
authors.lastname: Ye
authors.affiliation: National Maize Improvement Centre of China, China Agricultural University, Beijing 100193, China.
authors.forename: Jinsheng
authors.initials: J
authors.lastname: Lai
authors.affiliation: College of Agronomy, Synergetic Innovation Center of Henan Grain Crops and National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengzhou 450002, China.
authors.forename: Jianyu
authors.initials: J
authors.lastname: Wu
authors.affiliation: Department of Agronomy, Iowa State University, Ames, IA 50011, USA. Electronic address: thomasl@iastate.edu.
authors.forename: Thomas
authors.initials: T
authors.lastname: Lübberstedt
authors.affiliation: National Maize Improvement Centre of China, China Agricultural University, Beijing 100193, China. Electronic address: mxu@cau.edu.cn.
authors.forename: Mingliang
authors.initials: M
authors.lastname: Xu
mesh_terms: D003593:Cytoplasm / Q000378:metabolism; D060467:Disease Resistance / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D010935:Plant Diseases / Q000821:virology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D017800:Potyvirus / Q000472:pathogenicity*; D012367:RNA, Viral / Q000235:genetics; D013879:Thioredoxins / Q000235:genetics / Q000378:metabolism*; D003313:Zea mays / Q000235:genetics / Q000378:metabolism* / Q000821:virology*
chemical_list: D010940:Plant Proteins; D012367:RNA, Viral; D013879:Thioredoxins
keywords: h-type thioredoxin; maize; quantitative resistance gene; sugarcane mosaic virus