Heme oxygenase is involved in H(2)O          (2)-induced lateral root formation in apocynin-treated rice.
KEY MESSAGE                 :                                     Apocynin is a natural organic compound structurally related to vanillin. We demonstrated that hydrogen peroxide and heme oxygenase participated in apocynin-induced lateral root formation in rice.                                                                  Apocynin, also known as acetovanillone, is a natural organic compound structurally related to vanillin. Information concerning the effect of apocynin on plants is limited. In this study, we examined the effect of apocynin on lateral root (LR) formation in rice. Treatment with apocynin induced LR formation and increased H(2)O(2) production, but had no effect on nitric oxide production. Diphenyleneiodonium chloride, an inhibitor of H(2)O(2) generating NADPH oxidase, was effective in reducing apocynin-induced H(2)O(2) production and LR formation. Apocynin treatment also increased superoxide dismutase activity and decreased catalase activity. H(2)O(2) application was able to increase the number of LRs. Moreover, H(2)O(2) production caused by H(2)O(2) and apocynin was localized in the root area corresponding to the LR emergence. Treatment with H(2)O(2) and apocynin also increased heme oxygenase (HO) activity and induced OsHO1 mRNA expression. Lateral root formation and HO activity induced by H(2)O(2) and apocynin were reduced by Zn protoporphyrin IX (the specific inhibitor of HO). Our data suggest that both H(2)O(2) and HO are required for apocynin-induced LR formation in rice.
Department of Agronomy, National Taiwan University, Taipei, Taiwan, ROC.
Yi-Hsuan
YH
Chen
Yun-Yang
YY
Chao
Yun Yen
YY
Hsu
Ching Huei
CH
Kao
D000098:Acetophenones / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D002374:Catalase / Q000187:drug effects / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism* / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism / Q000494:pharmacology; D012275:Oryza / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D012333:RNA, Messenger / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D036226:Seedlings / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D013482:Superoxide Dismutase / Q000187:drug effects / Q000378:metabolism
D000098:Acetophenones; D000975:Antioxidants; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D009569:Nitric Oxide; C056165:acetovanillone; D006861:Hydrogen Peroxide; D002374:Catalase; D051547:Heme Oxygenase-1; D013482:Superoxide Dismutase