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Title: R2R3‐MYB genes control petal pigmentation patterning in Clarkia gracilis ssp. sonomensis (Onagraceae)
Summary

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 inClarkia gracilisssp.sonomensis.

We identified an R2R3‐MYB transcription factor (CgsMYB12) responsible for anthocyanin pigmentation of the basal region (‘cup’) in the petal ofC.gracilisssp.sonomensis. A functional mutation inCgsMYB12creates a white cup on a pink petal background. Additionally, we found that twoR2R3‐MYBgenes (CgsMYB6andCgsMYB11) are also involved in petal background pigmentation. Each of these threeR2R3‐MYBgenes exhibits a different spatiotemporal expression pattern. The functionality of theseR2R3‐MYBgenes was confirmed through stable transformation ofArabidopsis.

Distinct spatial patterns ofR2R3‐MYBexpression have created the possibility that pigmentation in different sections of the petal can evolve independently. This finding suggests that recent gene duplication has been central to the evolution of petal pigmentation patterning inC. gracilisssp.sonomensis.

 
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PAR ID:
10454664
Author(s) / Creator(s):
 ;  
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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