Shu Pan, Li Yujing, Sheng Jiping, Shen Lin
College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
School of Agricultural Economics and Rural Development, Renmin University of China, Beijing 100872, China.
J Agric Food Chem. 2023 Apr 6. doi: 10.1021/acs.jafc.2c08723.
Mitogen-activated protein kinase (MAPK) cascades and ethylene are crucial for plant growth, development, and stress responses, but their potential mechanisms in cold resistance remain unclear. We revealed that transcript levels were dramatically induced by cold treatment in an ethylene-dependent manner. Under cold stress, the proline content of -overexpression fruit was 96.5 and 115.9% higher than that of wild-type fruit (WT), respectively, while the ion leakage was 37.3 and 32.5% lower than that of WT. RNA sequencing revealed that overexpression of caused upregulation of genes that are enriched in the ethylene-activated signaling pathway (GO:0009873), cold signaling pathway (GO:0009409), and heat signaling pathway (GO:0009408). RT-qPCR demonstrated that the expression levels of , , , , , , and in the fruits were consistent with the RNA sequencing results. Meanwhile, the knockout of reduced the ethylene content, ACC content, and ACS activity. Moreover, the knockout of reduced the positive effect of ethylene in cold stress, while suppressing the expression of and . In conclusion, our study demonstrated a novel mechanism by which positively regulates the ethylene production of postharvest tomato fruits and is involved in ethylene-mediated cold tolerance.
丝裂原活化蛋白激酶（MAPK）级联反应和乙烯对于植物的生长、发育及胁迫响应至关重要，但其在抗寒方面的潜在机制仍不清楚。我们发现转录水平在冷处理下以乙烯依赖的方式显著诱导。在冷胁迫下，过表达果实的脯氨酸含量分别比野生型果实（WT）高96.5%和115.9%，而离子渗漏比WT分别低37.3%和32.5%。RNA测序显示的过表达导致了在乙烯激活信号通路（GO:0009873）、冷信号通路（GO:0009409）和热信号通路（GO:0009408）中富集的基因上调。RT-qPCR表明果实中、、、、、和的表达水平与RNA测序结果一致。同时，的敲除降低了乙烯含量、ACC含量和ACS活性。此外，的敲除降低了乙烯在冷胁迫中的积极作用，同时抑制了和的表达。总之，我们的研究证明了一种新机制，即正向调节采后番茄果实的乙烯生成并参与乙烯介导的耐寒性。
