Department of Horticulture, Zijingang Campus, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, China.
Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, 866 Yuhangtang Road, Hangzhou 310058, China.
Plant Cell Physiol. 2017 Nov 1;58(11):1963-1975. doi: 10.1093/pcp/pcx134.
The participation of nitric oxide (NO) in the responses of plants towards biotic and abiotic stresses is well established. However, the mechanism involved particularly in cold acclimation-induced chilling tolerance remains elusive. Here we show the cold acclimation induced-chilling tolerance was associated with inductions of nitrate reductase (NR)-dependent NO production, S-nitrosylated glutathione reductase (GSNOR) activity and mitogen-activated protein kinases MPK1/2 activation in tomato plants. Silencing of NR resulted in decreased GSNOR activity and MPK1/2 activation, which subsequently compromised cold acclimation-induced chilling tolerance. By contrast, silencing of GSNOR caused decreased NR activity, increased NO accumulation and MPK1/2 activation, and enhanced cold acclimation-induced chilling tolerance. Furthermore, co-silencing of MPK1 and MPK2 attenuated the NR-dependent NO production and cold acclimation-induced tolerance to chilling. Results from present study suggest the importance of MPK1/2 for the induction of NR-dependent NO generation, while the accumulation of nitrosylated glutathione from NO-derived reactive nitrogen species could potentially S-nitrosylate NR. These findings provide new insight into the crosstalk of NO and MPK1/2 in cold acclimation-induced chilling tolerance in tomato plants.
一氧化氮（NO）参与植物对生物和非生物胁迫的反应已得到充分证实。然而，特别是在冷驯化诱导的耐冷性方面，所涉及的机制仍不清楚。在这里，我们表明冷驯化诱导的耐冷性与番茄植株中硝酸盐还原酶（NR）依赖性 NO 产生、S-亚硝基谷胱甘肽还原酶（GSNOR）活性和丝裂原激活蛋白激酶 MPK1/2 激活的诱导有关。NR 的沉默导致 GSNOR 活性和 MPK1/2 激活降低，从而损害了冷驯化诱导的耐冷性。相比之下，GSNOR 的沉默导致 NR 活性降低、NO 积累增加和 MPK1/2 激活增强，从而增强了冷驯化诱导的耐冷性。此外，MPK1 和 MPK2 的共沉默减弱了 NR 依赖性 NO 产生和冷驯化诱导的耐冷性。本研究的结果表明了 MPK1/2 在诱导 NR 依赖性 NO 生成中的重要性，而来自 NO 衍生的活性氮物种的谷胱甘肽的亚硝基化可能潜在地使 NR 发生 S-亚硝基化。这些发现为番茄植物中冷驯化诱导的耐冷性中 NO 和 MPK1/2 的串扰提供了新的见解。
