Phenolamides(PAs), a diverse group of specialized metabolites, including hydroxycinnamoylputrescine(HP), hydroxycinnamoylagmatine, and hydroxycinnamoyltryptamine, are important in plant resistance to biotic stress. Ho...Phenolamides(PAs), a diverse group of specialized metabolites, including hydroxycinnamoylputrescine(HP), hydroxycinnamoylagmatine, and hydroxycinnamoyltryptamine, are important in plant resistance to biotic stress. However, the genes involved in the biosynthesis and modulation of PAs have not been fully elucidated. This study identified an HP biosynthetic gene cluster in rice(Oryza sativa) comprising one gene(Os ODC) encoding a decarboxylase and two tandem-duplicated genes(Os PHT3 and Os PHT4)encoding putrescine hydroxycinnamoyl acyltransferases coexpressed in different tissues. Os ODC catalyzes the conversion of ornithine to putrescine, which is used in HP biosynthesis involving Os PHT3 and Os PHT4. Os PHT3 or Os PHT4 overexpression causes HP accumulation and cell death and putrescine hydroxycinnamoyl acyltransferases(PHT) activity-dependent resistance against the fungal pathogen Magnaporthe oryzae. Os ODC overexpression plants also confer enhanced resistance to M. oryzae.Notably, the basic leucine zipper transcription factor APIP5, a negative regulator of cell death, directly binds to the Os PHT4 promoter, repressing its transcription. Moreover, APIP5 suppression induces Os PHT4 expression and HP accumulation. Comparative genomic analysis revealed that the HP biosynthetic gene cluster is conserved in monocots. These results characterized a previously unidentified monocot-specific gene cluster that is involved in HP biosynthesis and contributes to defense and cell death in rice.展开更多
基金supported by grants from the National Natural Science Foundation of China (31822041 and 31972225)the National Key Research and Development Program of China (2016YFD0100600) to Yuese Ning+5 种基金the National Natural Science Foundation of China (U20A2021) to Ruyi Wangthe National Natural Science Foundation of China (31801692) to Fan Zhangthe State Key Program of National Natural Science Foundation of China (31530052)the National Science Fund for Distinguished Young Scholars (31625021)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (31821005)the Hainan University Start up Fund (KYQD(ZR)1866 to Jie Luo。
文摘Phenolamides(PAs), a diverse group of specialized metabolites, including hydroxycinnamoylputrescine(HP), hydroxycinnamoylagmatine, and hydroxycinnamoyltryptamine, are important in plant resistance to biotic stress. However, the genes involved in the biosynthesis and modulation of PAs have not been fully elucidated. This study identified an HP biosynthetic gene cluster in rice(Oryza sativa) comprising one gene(Os ODC) encoding a decarboxylase and two tandem-duplicated genes(Os PHT3 and Os PHT4)encoding putrescine hydroxycinnamoyl acyltransferases coexpressed in different tissues. Os ODC catalyzes the conversion of ornithine to putrescine, which is used in HP biosynthesis involving Os PHT3 and Os PHT4. Os PHT3 or Os PHT4 overexpression causes HP accumulation and cell death and putrescine hydroxycinnamoyl acyltransferases(PHT) activity-dependent resistance against the fungal pathogen Magnaporthe oryzae. Os ODC overexpression plants also confer enhanced resistance to M. oryzae.Notably, the basic leucine zipper transcription factor APIP5, a negative regulator of cell death, directly binds to the Os PHT4 promoter, repressing its transcription. Moreover, APIP5 suppression induces Os PHT4 expression and HP accumulation. Comparative genomic analysis revealed that the HP biosynthetic gene cluster is conserved in monocots. These results characterized a previously unidentified monocot-specific gene cluster that is involved in HP biosynthesis and contributes to defense and cell death in rice.
