title: Signal transduction and regulation of IbpreproHypSys in sweet potato.
abstract: Hydroxyproline-rich glycopeptides (HypSys) are small signalling peptides containing 18-20 amino acids. The expression of IbpreproHypSys, encoding the precursor of IbHypSys, was induced in sweet potato (Ipomoea batatas cv. Tainung 57) through wounding and IbHypSys treatments by using jasmonate and H2 O2 . Transgenic sweet potatoes overexpressing (OE) and silencing [RNA interference (RNAi)] IbpreproHypSys were created. The expression of the wound-inducible gene for ipomoelin (IPO) in the local and systemic leaves of OE plants was stronger than the expression in wild-type (WT) and RNAi plants after wounding. Furthermore, grafting experiments indicated that IPO expression was considerably higher in WT stocks receiving wounding signals from OE than from RNAi scions. However, wounding WT scions highly induced IPO expression in OE stocks. These results indicated that IbpreproHypSys expression contributed towards sending and receiving the systemic signals that induced IPO expression. Analysing the genes involved in the phenylpropanoid pathway demonstrated that lignin biosynthesis was activated after synthetic IbHypSys treatment. IbpreproHypSys expression in sweet potato suppressed Spodoptera litura growth. In conclusion, wounding induced the expression of IbpreproHypSys, whose protein product was processed into IbHypSys. IbHypSys stimulated IbpreproHypSys and IPO expression and enhanced lignin biosynthesis, thus protecting plants from insects.
authors.affiliation: Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan.
authors.forename: Yu-Chi
authors.initials: YC
authors.lastname: Li
authors.affiliation: Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan.|Department of Plant Biochemistry, Center for Plant Molecular Biology, University of Tuebingen, Tuebingen, 72076, Germany.
authors.forename: Wei-Lin
authors.initials: WL
authors.lastname: Wan
authors.affiliation: Department of Life Sciences, National Chung Hsing University, Taichung, 40227, Taiwan.
authors.forename: Jeng-Shane
authors.initials: JS
authors.lastname: Lin
authors.affiliation: Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan.
authors.forename: Yun-Wei
authors.initials: YW
authors.lastname: Kuo
authors.affiliation: Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan.
authors.forename: Yu-Chi
authors.initials: YC
authors.lastname: King
authors.affiliation: Department of Biotechnology, National Kaohsiung Normal University, Kaohsiung, 82444, Taiwan.
authors.forename: Yu-Chi
authors.initials: YC
authors.lastname: Chen
authors.affiliation: Institute of Plant Biology and Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan.
authors.forename: Shih-Tong
authors.initials: ST
authors.lastname: Jeng
mesh_terms: D000818:Animals; D003517:Cyclopentanes / Q000378:metabolism; D006020:Glycopeptides / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism; D027723:Ipomoea batatas / Q000378:metabolism*; D008031:Lignin / Q000096:biosynthesis; D054883:Oxylipins / Q000378:metabolism; D030821:Plants, Genetically Modified; D015398:Signal Transduction; D018411:Spodoptera
chemical_list: D003517:Cyclopentanes; D006020:Glycopeptides; D054883:Oxylipins; C011006:jasmonic acid; D008031:Lignin; D006861:Hydrogen Peroxide
keywords: hormones; insect interaction; mechanical; mechanical wounding response; oxidative stress; signalling