National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
Plant Cell. 2010 Sep;22(9):3164-76. doi: 10.1105/tpc.110.078022. Epub 2010 Sep 17.
Pathogen effectors are virulence factors causing plant diseases. How the host targets of these effectors facilitate pathogen infection is largely unknown. An effector of Xanthomonas oryzae pv oryzae (Xoo) transcriptionally activates rice (Oryza sativa) susceptibility gene Xa13 to cause bacterial blight disease. Xa13 encodes an indispensable plasma membrane protein of the MtN3/saliva family, which is prevalent in eukaryotes with unknown biochemical function. We show that the XA13 protein cooperates with two other proteins, COPT1 and COPT5, to promote removal of copper from xylem vessels, where Xoo multiplies and spreads to cause disease. Copper, an essential micronutrient of plants and an important element for a number of pesticides in agriculture, suppresses Xoo growth. Xoo strain PXO99 is more sensitive to copper than other strains; its infection of rice is associated with activation of XA13, COPT1, and COPT5, which modulate copper redistribution in rice. The involvement of XA13 in copper redistribution has led us to propose a mechanism of bacterial virulence.
病原体效应子是引起植物病害的毒力因子。这些效应子的宿主靶标如何促进病原体感染在很大程度上是未知的。稻黄单胞菌 pv 稻（Xoo）的一种效应子转录激活水稻（Oryza sativa）感病基因 Xa13 ，导致细菌性条斑病。Xa13 编码 MtN3/唾液家族的一种必需质膜蛋白，该蛋白在真核生物中普遍存在，但生化功能未知。我们表明，XA13 蛋白与另外两种蛋白 COPT1 和 COPT5 合作，促进木质部导管中铜的去除，Xoo 在木质部导管中繁殖和扩散，导致疾病。铜是植物必需的微量元素，也是农业中许多杀虫剂的重要元素，它抑制 Xoo 的生长。菌株 PXO99 比其他菌株对铜更敏感；它对水稻的感染与 XA13、COPT1 和 COPT5 的激活有关，这些蛋白调节了水稻中铜的再分配。XA13 参与铜的再分配，这使我们提出了一种细菌毒力的机制。
