Patterned leaf coloration in plants generates remarkable diversity in nature, but the underlying mechanisms remain largely unclear. Here, using RH1 mainly functions as an anthocyanin biosynthesis activator that specifically determines leaf marking formation depending on its C‐terminal activation motif. RH1 physically interacts with the Our findings reveal the molecular mechanism of the antagonistic gene paralogs RH1 and RH2 in determining anthocyanin leaf markings in
Petal pigmentation patterning is widespread in flowering plants. The genetics of these pattern elements has been of great interest for understanding the evolution of phenotypic diversification. Here, we investigate the genetic changes responsible for the evolution of an unpigmented petal element on a colored background. We used transcriptome analysis, gene expression assays, cosegregation in F2plants and functional tests to identify the gene(s) involved in petal coloration in We identified an R2R3‐MYB transcription factor (CgsMYB12) responsible for anthocyanin pigmentation of the basal region (‘cup’) in the petal of Distinct spatial patterns of
- NSF-PAR ID:
- 10454664
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 229
- Issue:
- 2
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 1147-1162
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary Medicago truncatula leaf marking as a model, we show that the classicM. truncatula leaf anthocyanin spot trait depends on two R2R3 MYB paralogous regulators, RED HEART1 (RH1) and RH2.M. truncatula bHLH protein MtTT8 and the WDR family member MtWD40‐1, and this interaction facilitates RH1 function in leaf anthocyanin marking formation. RH2 has lost transcriptional activation activity, due to a divergent C‐terminal domain, but retains the ability to interact with the same partners, MtTT8 and MtWD40‐1, as RH1, thereby acting as a competitor in the regulatory complex and exerting opposite effects. Moreover, our results demonstrate that RH1 can activate its own expression and that RH2‐mediated competition can repressRH1 expression.M. truncatula , providing a multidimensional paralogous–antagonistic regulatory paradigm for fine‐tuning patterned pigmentation. -
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