Jiao Caifeng, Sun Jing
School of Horticulture, Anhui Agricultural University, Hefei, China.
College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, China.
Front Plant Sci. 2025 Jun 13;16:1603423. doi: 10.3389/fpls.2025.1603423. eCollection 2025.
The cold chain system is extensively used to lower the quality deterioration in postharvest fruits. However, the occurrence of chilling injury (CI) is a common phenomenon in peach fruits, consequently compromising their market value.
Cold tolerance was boosted by glycine betaine (GB) supplementation. GB treatment promoted the thioredoxin h9 (PpTrxh9) expression and ameliorated oxidative injury. Using assays such as yeast two-hybrid, co-immunoprecipitation, pull-down, and bimolecular fluorescence complementation, SHAGGY-related protein kinase a (PpSKa) was verified as a protein interacting with PpTrxh9. GB treatment elevated the PpSKa expression. The overexpression of PpSKa in tomato fruits decreased the cold sensitivity and oxidative damage, whereas virus-induced gene silencing of PpSKa in peach fruits aggravated the CI progression and oxidative damage. PpSKa was found to phosphorylate PpTrxh9 in the kinase assay. Moreover, PpSKa-overexpressed tomato fruits exhibited higher SlTrxh9 expression, whereas the PpSKa-RNAi peach fruit exhibited lower PpTrxh9 expression.
Taken together, PpSKa decreased the development of CI by improving the expression of PpTrxh9 in peach fruits.
冷链系统被广泛用于降低采后果实的品质劣化。然而，冷害（CI）的发生在桃果实中是一种常见现象，从而损害了它们的市场价值。
通过补充甘氨酸甜菜碱（GB）提高了耐寒性。GB处理促进了硫氧还蛋白h9（PpTrxh9）的表达并减轻了氧化损伤。通过酵母双杂交、免疫共沉淀、下拉和双分子荧光互补等实验，证实SHAGGY相关蛋白激酶a（PpSKa）是一种与PpTrxh9相互作用的蛋白。GB处理提高了PpSKa的表达。番茄果实中PpSKa的过表达降低了冷敏感性和氧化损伤，而桃果实中PpSKa的病毒诱导基因沉默加剧了冷害进程和氧化损伤。在激酶实验中发现PpSKa使PpTrxh9磷酸化。此外，PpSKa过表达的番茄果实表现出更高的SlTrxh9表达，而PpSKa-RNAi桃果实表现出更低的PpTrxh9表达。
综上所述，PpSKa通过提高桃果实中PpTrxh9的表达降低了冷害的发展。
