The ApWRKY26/ApERF4-ApMYB2 module regulates anthocyanin accumulation for the seasonal leaf color transition in Acer palmatum

Abstract

Acer palmatum ‘Duocai’ is an excellent ornamental cultivar maintained through asexual propagation. In spring and autumn, it exhibits red leaves, and in summer, it displays green leaves. To investigate the genetic and epigenetic regulation underlying these seasonal pigmentation shifts, we implemented a comprehensive multi-omics approach. Metabolomic profiling identified cyanidin-3-O-glucoside as the predominant biochemical factor governing seasonal leaf color transitions. RNA-seq, ATAC-seq, Hi-C, and WGBS were utilized to examine transcriptomic and chromatin remodeling dynamics. Multi-omics regulatory network analysis identified ApMYB2 as a key transcription factor (TF) affecting anthocyanin accumulation by regulating ApF3'H2 expression. Functional analyses demonstrated that the TF ApWRKY26 positively modulates ApMYB2 expression, while ApERF4 exerts an inhibitory effect on its expression. These regulatory interactions were corroborated by seasonal RNA-seq-based correlation analyses. Genetic manipulation experiments, including overexpression and silencing of these genes in A. palmatum, provided empirical evidence supporting their functional roles in the anthocyanin biosynthetic pathway. Together, our study elucidates the molecular mechanism by which ApWRKY26 and ApERF4 coordinate the activity of ApMYB2 to govern seasonal anthocyanin synthesis in A. palmatum foliage.

Acknowledgements

This research was supported by the National Natural Science Foundation of China (Project No. 32301660 and 32271914).

Zhu Chen and Jie Ren designed and supervised the research and wrote the manuscript; Zhu Chen, Faheem Afzal Shah, Guo Wei, and Xin Meng performed experiments; Zhu Chen and Xiaoyu Lu performed bioinformatics analysis and visualized datasets; Lu Zhu and Qiuyue Ma did the sample collection. All contributors participated in interpreting the data and revising the manuscript.

Data availability

All sequencing datasets generated during this study are publicly accessible through the NCBI Sequence Read Archive (SRA) under accession code PRJNA1163018.

Conflicts of interest statement

The authors affirm no conflicts of interest related to this work.

Supplementary material

Supplementary material is available at Horticulture Research online.

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