Department of Life Science and Institute of Plant Biology, National Taiwan University, Taipei 106, Taiwan.
J Exp Bot. 2010 Feb;61(4):995-1002. doi: 10.1093/jxb/erp363. Epub 2009 Dec 10.
The non-protein amino acid beta-aminobutyric acid (BABA) enhances Arabidopsis resistance to microbial pathogens and abiotic stresses through potentiation of the Arabidopsis defence responses. In this study, it is shown that BABA induces the stress-induced morphogenic response (SIMR). SIMR is observed in plants exposed to sub-lethal stress conditions. Anthocyanin, a known modulator of stress signalling, was also found to accumulate in BABA-treated Arabidopsis. These data and a previous microarray study indicate that BABA induces a stress response in Arabidopsis. High concentrations of amino acids, except for L-glutamine, cause a general amino acid stress inhibition. General amino acid inhibition is prevented by the addition of L-glutamine. L-Glutamine was found to inhibit the BABA-mediated SIMR and anthocyanin accumulation, suggesting that the non-protein amino acid BABA causes a general amino acid stress inhibition in Arabidopsis. L-Glutamine also blocked BABA-induced resistance to heat stress and to the virulent bacterial pathogen Pseudomonas syringae pv. tomato DC3000. During bacterial infection, priming of the salicylic acid-dependent defence marker PR1 was abolished by L-glutamine treatment. These results indicate that L-glutamine removal of the BABA-mediated stress response is concomitant with L-glutamine inhibition of BABA priming and BABA-induced resistance.
非蛋白氨基酸β-氨基丁酸（BABA）通过增强拟南芥的防御反应来提高其对微生物病原体和非生物胁迫的抗性。在本研究中，表明 BABA 诱导胁迫诱导形态发生响应（SIMR）。SIMR 可在暴露于亚致死胁迫条件下的植物中观察到。花青素，一种已知的应激信号调节剂，也被发现积累在 BABA 处理的拟南芥中。这些数据和以前的微阵列研究表明，BABA 诱导拟南芥产生应激反应。除 L-谷氨酰胺外，高浓度的氨基酸会引起一般氨基酸应激抑制。添加 L-谷氨酰胺可防止一般氨基酸抑制。发现 L-谷氨酰胺抑制 BABA 介导的 SIMR 和花青素积累，表明非蛋白氨基酸 BABA 引起拟南芥的一般氨基酸应激抑制。L-谷氨酰胺还阻断了 BABA 诱导的对热应激和强毒力细菌病原体丁香假单胞菌 pv.番茄 DC3000 的抗性。在细菌感染期间，L-谷氨酰胺处理消除了水杨酸依赖的防御标记物 PR1 的引发。这些结果表明，L-谷氨酰胺去除 BABA 介导的应激反应伴随着 L-谷氨酰胺抑制 BABA 引发和 BABA 诱导的抗性。
