Style length is a major determinant of breeding strategies in flowering plants and can vary dramatically between and within species. However, little is known about the genetic and developmental control of style elongation. We characterized the role of two classes of leaf adaxial–abaxial polarity factors, SUPPRESSOR OF GENE SILENCING3 (SGS3) and the YABBY family transcription factors, in the regulation of style elongation in Loss of We suggest that auxin signaling plays a central role in style elongation and that the way in which auxin signaling controls the different cell division and elongation patterns underpinning natural style length variation is a major question for future research.
Fusion of petals to form a corolla tube is considered a key innovation contributing to the diversification of many flowering plant lineages. Corolla tube length often varies dramatically among species and is a major determinant of pollinator preference. However, our understanding of the developmental dynamics underlying corolla tube length variation is very limited. Here we examined corolla tube growth in the
- Award ID(s):
- 1755373
- NSF-PAR ID:
- 10452604
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Evolution & Development
- Volume:
- 23
- Issue:
- 3
- ISSN:
- 1520-541X
- Page Range / eLocation ID:
- p. 244-255
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary Mimulus lewisii . We also examined the spatiotemporal patterns of auxin response during style development.SGS3 function led to reduced style length via limiting cell division, and downregulation ofYABBY genes by RNA interference resulted in shorter styles by decreasing both cell division and cell elongation. We discovered an auxin response minimum between the stigma and ovary during the early stages of pistil development that marks style differentiation. Subsequent redistribution of auxin response to this region was correlated with style elongation. Auxin response was substantially altered when bothSGS3 andYABBY functions were disrupted. -
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