The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, 27 Shandanan Road, Jinan, Shandong 250100, People's Republic of China.
Plant Physiol. 2014 Feb;164(2):1068-76. doi: 10.1104/pp.113.227595. Epub 2013 Dec 10.
One of the two branches of the α-linolenic acid metabolism pathway is catalyzed by 12-oxo-phytodienoic acid reductase I, and the other is involved in jasmonic acid (JA) synthesis. The former is known to be active in the response to salinity tolerance in wheat (Triticum aestivum), but the participation of the latter in this response has not been established as yet. Here, the salinity-responsive bread wheat gene TaAOC1, which encodes an allene oxide cyclase involved in the α-linolenic acid metabolism pathway, was constitutively expressed in both bread wheat and Arabidopsis (Arabidopsis thaliana). In both species, transgenic lines exhibited an enhanced level of tolerance to salinity. The transgenic plants accumulated a higher content of JA and developed shorter roots. Both the shortened roots and the salinity tolerance were abolished in a background lacking a functional AtMYC2, a key component of the JA and abscisic acid signaling pathway, but were still expressed in a background deficient with respect to abscisic acid synthesis. We provide the first evidence, to our knowledge, suggesting that JA is also involved in the plant salinity response and that the α-linolenic acid metabolism pathway has a regulatory role over this response.
α-亚麻酸代谢途径的两个分支之一由 12-氧代-植物二烯酸还原酶 I 催化，另一个分支参与茉莉酸 (JA) 的合成。前者已知在小麦（Triticum aestivum）对盐度耐受性的反应中是活跃的，但后者在这种反应中的参与尚未得到证实。在这里，与α-亚麻酸代谢途径有关的参与 12-氧代-植物二烯酸还原酶 I 的编码基因 TaAOC1 是一个响应盐度的面包小麦基因，在面包小麦和拟南芥（Arabidopsis thaliana）中均组成型表达。在这两个物种中，转基因系表现出对盐度更高的耐受性。转基因植物积累了更高水平的 JA，并且根更短。在缺乏功能性 AtMYC2 的背景下，缩短的根和对盐度的耐受性都被消除了，AtMYC2 是 JA 和脱落酸信号途径的关键组成部分，但在缺乏脱落酸合成的背景下仍然表达。我们提供了第一个证据，据我们所知，表明 JA 也参与植物的盐度反应，并且α-亚麻酸代谢途径对这种反应具有调节作用。
