Analysis of the HD-Zip I transcription factor family in and functional research of in tanshinone synthesis.

BACKGROUND

The homeodomain-leucine zipper I (HD-Zip I) transcription factor is a plant-specific protein that plays an essential role in the abiotic stress response of plants. Research on the HD-Zip I family in is still lacking.

METHODS AND RESULTS

In this study, a total of 25 SmHD-Zip I proteins were identified. Their characterizations, phylogenetic relationships, conserved motifs, gene structures, and cis-elements were analyzed comprehensively using bioinformatics methods. Expression profiling revealed that genes exhibited distinctive tissue-specific patterns and divergent responses to ABA, PEG, and NaCl stresses. responded the most strongly to ABA, PEG, and NaCl, so it was used for transgenic experiments. The overexpression of significantly increased the content of cryptotanshinone, dihydrotanshinone I, tanshinone I, and tanshinone IIA by 2.89-fold, 1.85-fold, 2.14-fold, and 8.91-fold compared to the wild type, respectively. Moreover, in the tanshinone biosynthetic pathways, the overexpression of up-regulated the expression levels of , , , , , , , , and compared with the wild type.

CONCLUSIONS

This study provides information the possible functions of the HD-Zip I family and lays a theoretical foundation for clarifying the functional mechanism of the gene in regulating the synthesis of tanshinone in .