Multifaceted roles of LhWRKY44 in promoting anthocyanin accumulation in Asiatic hybrid lilies (Lilium spp.)

Mengmeng Bi; Rui Liang; Jiawen Wang; Yuxiao Qu; Xin Liu; Yuwei Cao; Guoren He; Yue Yang; Panpan Yang; Leifeng Xu; Jun Ming

doi:10.1093/hr/uhad167

Multifaceted roles of LhWRKY44 in promoting anthocyanin accumulation in Asiatic hybrid lilies (Lilium spp.)

Hortic Res. 2023 Aug 22;10(9):uhad167. doi: 10.1093/hr/uhad167. eCollection 2023 Sep.

Authors

Mengmeng Bi¹, Rui Liang^{1

2}, Jiawen Wang¹, Yuxiao Qu¹, Xin Liu^{1

3}, Yuwei Cao^{1

4}, Guoren He^{1

5}, Yue Yang¹, Panpan Yang¹, Leifeng Xu¹, Jun Ming¹

Affiliations

¹ State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
² College of Horticulture, Shanxi Agricultural University, Taigu, 030031, China.
³ College of Landscape architecture and Forestry, Qingdao Agricultural University, Qingdao, 266109, China.
⁴ College of Chemistry and Life Science, Gannan Normal University, Ganzhou, 341000, China.
⁵ Shanghai Key Laboratory of Plant Molecular Science, College of Life Sciences, Shanghai Normal University, Shanghai, 200233, China.

Abstract

The Asiatic hybrid lily (Lilium spp.) is a horticultural crop with high commercial value and diverse anthocyanin pigmentation patterns. However, the regulatory mechanism underlying lily flower color has been largely unexplored. Here, we identified a WRKY transcription factor from lily tepals, LhWRKY44, whose expression was closely associated with anthocyanin accumulation. Functional verification indicated that LhWRKY44 positively regulated anthocyanin accumulation. LhWRKY44 physically interacted with LhMYBSPLATTER and directly bound to the LhMYBSPLATTER promoter, which enhanced the effect of the LhMYBSPLATTER-LhbHLH2 MBW complex activator on anthocyanin accumulation. Moreover, EMSA and dual-luciferase assays revealed that LhWRKY44 activated and bound to the promoters of gene LhF3H and the intracellular anthocyanin-related glutathione S-transferase gene LhGST. Interestingly, our further results showed that LhWRKY44 participated in light and drought-induced anthocyanin accumulation, and improved the drought tolerance in lily via activating stress-related genes. These results generated a multifaceted regulatory mechanism for the LhWRKY44-meditaed enhancement by the environmental signal pathway of anthocyanin accumulation and expanded our understanding of the WRKY-mediated transcriptional regulatory hierarchy modulating anthocyanin accumulation in Asiatic hybrid lilies.