文献类型： 外文期刊

作者： Tian, Dagang ¹ ; Yang, Fang ² ; Niu, Yuqing ³ ; Lin, Yan ¹ ; Chen, Zaijie ¹ ; Li, Gang ¹ ; Luo, Qiong ⁴ ; Wang, Feng ¹ ; Wan ¹ ;

作者机构： 1.Fujian Acad Agr Sci, Fujian Key Lab Genet Engn Agr, Biotechnol Res Inst, Fuzhou 350003, Fujian, Peoples R China

2.Fujian Agr & Forestry Univ, Coll Life Sci, State Key Lab Ecol Pest Control Fujian & Taiwan C, Fuzhou 350002, Fujian, Peoples R China

3.Fujian Agr & Forestry Univ, Coll Agr, Minist Educ Genet Breeding & Multiple Utilizat Cr, Key Lab, Fuzhou 350002, Fujian, Peoples R China

4.Yunnan Agr Univ, Key Lab Agr Biodivers Plant Dis Management, Minist Educ, Kunming 650201, Yunnan, Peoples R China

5.Fujian Agr & Forestry Univ, Fujian Univ, Key Lab Plant Microbe Interact, Fuzhou 350002, Fujian, Peoples R China

关键词： Rice; Serotonin; Reactive oxygen species; PAMP-triggered immunity; Defense hormones; Pyricularia oryzae

期刊名称：BMC PLANT BIOLOGY （ 影响因子：4.215； 五年影响因子：4.96 ）

ISSN： 1471-2229

年卷期： 2020 年 20 卷 1 期

页码：

收录情况： SCI

摘要： Background Serotonin, originally identified as a neurotransmitter in mammals, functions as an antioxidant to scavenge cellular ROS in plants. In rice, the conversion of tryptamine to serotonin is catalyzed by SL (sekiguchi lesion), a member of cytochrome P450 monooxygenase family. The sl mutant, originated from rice cultivar Sekiguchi-asahi, exhibits spontaneous lesions, whereas its immune responses to pathogens have not been clearly characterized. Results Here we identified three allelic mutants of SL in an indica rice restore line Minghui 86 (MH86), named as sl-MH-1, - 2 and - 3, all of which present the typical lesions under normal growth condition. Compared with those in MH86, the serotonin content in sl-MH-1 is dramatically decreased, whereas the levels of tryptamine and L-trytophan are significantly increased. The sl-MH-1 mutant accumulates high H2O2 level at its lesion sites and is more sensitive to exogenous H2O2 treatment than the wild type. When treated with the reductant vitamin C (Vc), the lesion formation on sl-MH-1 leaves could be efficiently suppressed. In addition, sl-MH-1 displayed more resistant to both the blast fungus and blight bacteria, Pyricularia oryzae (P. oryzae, teleomorph: Magnaporthe oryzae) and Xanthomonas oryzae pv. Oryzae (Xoo), respectively. The pathogen-associated molecular patterns (PAMPs)-triggered immunity (PTI) responses, like reactive oxygen species (ROS) burst and callose deposition, were enhanced in sl-MH-1. Moreover, loss function of SL resulted in higher resting levels of the defense hormones, salicylic acid and jasmonic acid. The RNA-seq analysis indicated that after P. oryzae infection, transcription of the genes involved in reduction-oxidation regulation was the most markedly changed in sl-MH-1, compared with MH86. Conclusions Our results indicate that SL, involving in the final step of serotonin biosynthesis, negatively regulates rice resistance against (hemi)biotrophic pathogens via compromising the PTI responses and defense hormones accumulation.