Liu Hao, Guo Zhenhua, Gu Fengwei, Ke Shanwen, Sun Dayuan, Dong Shuangyu, Liu Wei, Huang Ming, Xiao Wuming, Yang Guili, Liu Yongzhu, Guo Tao, Wang Hui, Wang Jiafeng, Chen Zhiqiang
National Engineering Research Center of Plant Space Breeding, South China Agricultural University Guangzhou, China.
Department of Rice Breeding, Jiamusi Rice Research Institute of Heilongjiang Academy of Agricultural Sciences Jiamusi, China.
Front Plant Sci. 2017 Jan 10;7:2041. doi: 10.3389/fpls.2016.02041. eCollection 2016.
Although adenosine monophosphate (AMP) binding domain is widely distributed in multiple plant species, detailed molecular functions of AMP binding proteins (AMPBPs) in plant development and plant-pathogen interaction remain unclear. In the present study, we identified an AMPBP from a previous analysis of early responsive genes in rice during infection. is a homolog of Arabidopsis in rice, which encodes a 4-coumarate-Co-A ligase (4CL) like protein. A phylogenetic analysis showed that was most likely in an independent group. was localized to cytoplasm, and it could be expressed in various tissues. Histochemical staining of transgenic plants carrying promoter-driven GUS (β-glucuronidase) reporter gene suggested that was expressed in all tissues of rice. Furthermore, plants showed increased susceptibility to , and this finding was attributable to decreased expression of pathogen-related 1a () and low level of peroxidase (POD) activity. Moreover, over-expression resulted in increased content of HO, leading to programmed cell-death induced by reactive oxygen species (ROS). In addition, over-expression repressed the floret development, exhibiting dramatically twisted glume and decreased fertility rate of anther. Meanwhile, the expressions of lignin biosynthesis genes were significantly decreased in plants, thereby leading to reduced lignin content. Taken together, functioned as a negative regulator in rice blast resistance, floret development, and lignin biosynthesis. Our findings further expanded the knowledge in functions of AMBPs in plant floret development and the regulation of rice-fungus interaction.
尽管单磷酸腺苷（AMP）结合结构域广泛分布于多种植物物种中，但AMP结合蛋白（AMPBPs）在植物发育和植物-病原体相互作用中的详细分子功能仍不清楚。在本研究中，我们从之前对水稻感染早期响应基因的分析中鉴定出一种AMPBP。它是拟南芥在水稻中的同源物，编码一种类似4-香豆酸-CoA连接酶（4CL）的蛋白质。系统发育分析表明，它很可能属于一个独立的组。它定位于细胞质，并且可以在各种组织中表达。携带该基因启动子驱动的GUS（β-葡萄糖醛酸酶）报告基因的转基因植物的组织化学染色表明，该基因在水稻的所有组织中均有表达。此外，该基因过表达的植物对稻瘟病菌表现出更高的易感性，这一发现归因于病程相关蛋白1a（PR1a）表达的降低和过氧化物酶（POD）活性水平较低。此外，该基因的过表达导致过氧化氢（HO）含量增加，从而导致活性氧（ROS）诱导的程序性细胞死亡。此外，该基因的过表达抑制了小花发育，表现出颖壳明显扭曲和花药育性降低。同时，该基因过表达的植物中木质素生物合成基因的表达显著降低，从而导致木质素含量减少。综上所述，该基因在水稻抗稻瘟病、小花发育和木质素生物合成中起负调控作用。我们的研究结果进一步扩展了对AMPBPs在植物小花发育和水稻-真菌相互作用调控中功能的认识。
