Identification of bZIP Gene Family in Bergenia purpurascens and Functional Characterization of BpbZIP37 Under Heat Stress

<i>Bergenia purpurascens</i>, a perennial herb with significant medicinal value, thrives in harsh high-altitude environments but faces threats from global warming-induced heat stress. Basic leucine zipper (bZIP) transcription factors play crucial roles in plant growth, development, and stress responses, yet their functions in <i>B. purpurascens</i> remain unstudied. In this study, we identified 55 <i>bZIP</i> genes (<i>BpbZIP1-55</i>) from <i>B. purpurascens</i> transcriptome data. Expression pattern analyses identified several tissue-specific expressed <i>BpbZIP</i> genes, as well as eight heat stress-induced <i>BpbZIP</i> genes. Among them, <i>BpbZIP37</i> was the most significantly induced by heat stress and was used for functional characterization via over-expression in <i>Arabidopsis thaliana.</i> The results indicated that <i>BpbZIP37</i> can enhance the heat tolerance of plants by reducing reactive oxygen species accumulation and increasing activities of antioxidant enzymes. This study provides new insights into exploring the functions of <i>bZIP</i> genes in <i>B. purpurascens</i>, highlighting <i>BpbZIP37</i> as an important regulator of heat stress responses, which lays a foundation for plant breeding improvement and resource conservation tailored to climate change.