High-throughput identification of Prunus mume freezing-tolerance genes based on yeast screening system and functional verification of PmRCI2-3 in Arabidopsis

Plant Physiol Biochem. 2024 Dec 20:219:109431. doi: 10.1016/j.plaphy.2024.109431. Online ahead of print.

Abstract

Prunus mume tops the ten most famous flowers of China with high ornamental value, and low temperature is the main factor limiting its northward migration. Cold resistance improvement is one of the important breeding directions of Rosaceae ornamental plants, especially the Prunus mume. Here, 29 genes from P. mume were screened by yeast screening system under -20 °C for 96 h. Based on GO and KEGG analysis, rare cold-inducible 2 family gene member PmRCI2-3 was first cloned for functional verification. Subcellular localization results showed the PmRCI2-3 was located in the membrane structure, and GUS staining showed that the activity of the PmRCI2-3 promoter was spatiotemporally specific. Overexpression PmRCI2-3 in Arabidopsis thaliana can reduce plant damage at low temperatures. The expression levels of endogenous genes (AtCBF1, AtCBF2, AtCBF3, AtCOR15A, and AtRD29A) related to cold response were all up-regulated, except AtKIN was down-regulated. These results lay the foundation for further providing key candidate genes for cold resistance breeding of P. mume and other Prunus species.

Keywords: Cold stress; Functional verification; Prunus mume; RCI2 gene family; Yeast screening system.