Systematic Identification and Functional Analysis of the L. bZIP Gene Family Indicating That Overexpressed Enhances Drought Resistance.

Basic leucine zipper (bZIP) transcription factors play significant roles in plants' growth and development processes, as well as in response to biological and abiotic stresses. is one of the world's top three best-selling herbal medicines, mainly used to treat depression. However, there has been no systematic identification or functional analysis of the bZIP gene family in . In this study, 79 genes were identified. Based on phylogenetic analysis, the gene family was divided into ten groups, designated A-I and S. The physicochemical properties, gene structures, protein conserved motifs, and Gene Ontology enrichments of all were systematically analyzed. The expression patterns of all genes in different tissues of (i.e., root, stem, leaf, and flower) were analyzed by qRT-PCR, revealing the different expression patterns of under abiotic stresses. The HpbZIP69 protein is localized in the nucleus. According to the results of the yeast one-hybrid (Y1H) assays, HpbZIP69 can bind to the (N-acetylserotonin -methyltransferase) gene promoter (G-box -element) to activate its activity. Overexpressing in wild-type lines enhanced their tolerance to drought. The MDA and HO contents were significantly decreased, and the activity of superoxide dismutase (SOD) was considerably increased under the drought stress. These results may aid in additional functional studies of transcription factors, and in cultivating drought-resistant medicinal plants.