Prunus mume is an important woody plant that has high ornamental and economic value, widely distributed and used in landscape architecture in East Asia. In plants, basic (region) leucine zipper (bZIP) transcription factors play important regulatory roles in growth, development, dormancy and abiotic stress. To date, bZIP transcription factors have not been systematically studied in P. mume. In this study, 49 bZIP genes were first identified in P. mume, and the PmbZIP family was divided into 12 groups according to the grouping principles for the Arabidopsis thaliana bZIP family. For the first time, we constructed a detailed model of the PmbZIP domains (R-x₃N-x₇-R/K-x₂-K-x₆-L-x₆-L-x₆-L). Phylogenetic and synteny analyses showed that PmbZIPs duplication events might have occurred during the large-scale genome duplication events. A relatively short time of speciation and the finding that 91.84% of the bZIP genes formed orthologous pairs between P. mume and Prunus armeniaca provided evidence of a close relationship. Gene expression patterns were analysed in different tissues and periods, indicating that PmbZIP genes with the same motifs exhibited similar expression patterns. The gene expression results showed that PmbZIP31/36/41 genes played a more prominent role in the response to freezing stress than cold stress. The expression level of almost all subset III genes was upregulated under freezing treatment, especially after cold exposure. We analysed the gene expression patterns of PmbZIP12/31/36/41/48 and their responses to low-temperature stress, which provided useful resources for future studies on the cold/freezing-tolerant molecular breeding of P. mume.

梅梅是一种重要的木本植物，具有很高的观赏价值和经济价值，在东亚地区分布广泛，用于园林建筑。在植物中，碱性（区域）亮氨酸拉链（bZIP）转录因子在生长、发育、休眠和非生物胁迫中发挥重要的调节作用。迄今为止，尚未在P. mume中系统地研究 bZIP 转录因子。本研究首先在梅梅中鉴定出49个bZIP基因，根据拟南芥bZIP家族的分组原则，将PmbZIP家族分为12组。我们首次构建了 PmbZIP 域的详细模型（Rx ₃ N-x ₇ -R/Kx₂ -Kx ₆ -Lx ₆ -Lx ₆ -L)。系统发育和同线性分析表明，PmbZIPs复制事件可能发生在大规模基因组复制事件期间。相对较短的物种形成时间和 91.84% 的bZIP基因在P. mume和Prunus armeniaca之间形成直系同源对的发现提供了密切关系的证据。分析了不同组织和不同时期的基因表达模式，表明具有相同基序的PmbZIP基因表现出相似的表达模式。基因表达结果显示，PmbZIP31/36/41与冷应激相比，基因在对冷冻应激的反应中发挥了更突出的作用。在冷冻处理下，几乎所有子集 III 基因的表达水平都上调，尤其是在冷暴露后。我们分析了 PmbZIP12/31/36/41/48 的基因表达模式及其对低温胁迫的反应，为今后研究梅梅耐寒/耐冻分子育种提供了有用的资源。