Two MYB activators of anthocyanin biosynthesis exhibit specialized activities in petiole and fruit of diploid strawberry. (21st December 2022)

• Record Type: Journal Article
• Authors: Luo, Xi; Plunkert, Madison; Teng, Zi; Mackenzie, Kathryn; Guo, Lei; Luo, Yaguang; Hytönen, Timo; Liu, Zhongchi
• Editors: Costa, Fabrizio
• Is Part Of: Journal of experimental botany. Volume 74:Number 5(2023)
• Page Start: 1517
• Page End: 1531
• Publication Date: 2022-12-21
• Subjects: Anthocyanin -- diploid wild strawberry -- Fragaria vesca -- fruit -- MYB10 -- MYB10-Like -- petiole -- tissue-specific regulation; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/erac507
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract: The R2R3-MYB transcription factor FveMYB10 is a major regulator of anthocyanin pigmentation in the red fruits of strawberry. fvemyb10 loss-of-function mutants form yellow fruits but still accumulate purple-colored anthocyanins in the petioles, suggesting that anthocyanin biosynthesis is under distinct regulation in fruits and petioles. From chemical mutagenesis in the diploid wild strawberry Fragaria vesca, we identified a green petioles ( gp ) -1 mutant that lacks anthocyanins in petioles. Using mapping-by-sequencing and transient functional assays, we confirmed that the causative mutation resides in a FveMYB10-Like ( FveMYB10L ) gene and that FveMYB10 and FveMYB10L function independently in the fruit and petiole, respectively. In addition to their tissue-specific regulation, FveMYB10 and FveMYB10L respond differently to changes in light quality, produce distinct anthocyanin compositions, and preferentially activate different downstream anthocyanin biosynthesis genes in their respective tissues. This work identifies a new regulator of anthocyanin synthesis and demonstrates that two paralogous MYB genes with specialized functions enable tissue-specific regulation of anthocyanin biosynthesis in fruit and petiole tissues. Abstract : Strawberry plants accumulate anthocyanin in petioles through the action of the transcription factor MYB10-Like. Its expression and downstream target genes differ from MYB10, a regulator of pigmentation in the fruit.