Genome-wide identification of late embryogenesis abundant protein family and their key regulatory network in Pinus tabuliformis cold acclimation.

This article focuses on the genome-wide identification and functional analysis of the late embryogenesis abundant (LEA) protein family in Pinus tabuliformis, a conifer species important for studying cold acclimation. A total of 104 LEA genes were classified into eight subfamilies, with distinct physicochemical properties and conserved sequence structures, and many contained low-temperature responsive elements in their promoters. Transcriptome analyses across annual cycles and temperature gradients identified seven key LEA genes involved in cold acclimation, notably PtLEA22, whose overexpression enhanced freezing tolerance in Arabidopsis thaliana. Furthermore, the study demonstrated that the transcription factor PtDREB1 directly binds the PtLEA22 promoter to positively regulate its expression, suggesting a DREB–LEA regulatory module in conifers analogous to the CBF–COR pathway in angiosperms. These findings provide foundational insights into the molecular mechanisms of freezing tolerance and cold acclimation in gymnosperms.