College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China; Chengdu Agricultural College, Chengdu 611130, China; Key Laboratory of Horticulture Science for Southern Mountains Regions, Ministry of Education, Chongqing 400715, China.
College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China; Rice and Sorghum Institute, Sichuan Academy of Agricultural Sciences, Sichuan Deyang 618000, China.
Food Chem. 2020 Sep 15;324:126887. doi: 10.1016/j.foodchem.2020.126887. Epub 2020 Apr 21.
Epigenetic regulation and salt ions play essential roles in senescence control, but the underlying regulatory mechanism of senescence has not been thoroughly revealed in broccoli postharvest buds. Here, we found 200 mmol·L NaCl, 400 mmol·L KCl, 40 mmol·L CaCl and 0.5 μmol·L Trichostatin-A (TSA, a histone deacetylase inhibitor) delayed the bud senescence. They resulted in significantly inhibiting the malondialdehyde (MDA) content, and dramatically promoting the contents of superoxide dismutase (SOD), peroxidase (POD) and Chlorophyll. Furthermore, the expression of PHEOPHYTINASE (PPH) and NONYELLOWING (NYE1), but not SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1), were remarkably repressed by salt ions and TSA. Interestingly, HISTONE DEACETYLASE 9 (HDA9) and CATION/Ca EXCHANGER 1 (CCX1) were down-regulated by NaCl, CaCl and TSA. Further assays demonstrated that HDA9 could not interact with CCX1 promoter. It suggested that CCX1 along with HDA9 were involved in inhibiting the senescence of broccoli buds, and regulated aging by indirect interaction.
在衰老控制中，表观遗传调控和盐离子起着至关重要的作用，但在西兰花采后芽中，衰老的潜在调控机制尚未被彻底揭示。在这里，我们发现 200mmol·L NaCl、400mmol·L KCl、40mmol·L CaCl 和 0.5μmol·L Trichostatin-A（TSA，组蛋白去乙酰化酶抑制剂）延缓了芽的衰老。它们显著抑制了丙二醛（MDA）的含量，显著促进了超氧化物歧化酶（SOD）、过氧化物酶（POD）和叶绿素的含量。此外，质体黄质脱加氧酶（PPH）和非黄化（NYE1）的表达，而不是CONSTANS 1 过表达抑制因子（SOC1）的表达，被盐离子和 TSA 显著抑制。有趣的是，组蛋白去乙酰化酶 9（HDA9）和阳离子/Ca 交换器 1（CCX1）被 NaCl、CaCl 和 TSA 下调。进一步的实验表明，HDA9 不能与 CCX1 启动子相互作用。这表明 CCX1 与 HDA9 一起参与抑制西兰花芽的衰老，并通过间接相互作用调节衰老。
