Plants respond to neighbor shade by increasing stem and petiole elongation. Shade, sensed by phytochrome photoreceptors, causes stabilization of
Auxin is a hormone that is required for hypocotyl elongation during seedling development. In response to auxin, rapid changes in transcript and protein abundance occur in hypocotyls, and some auxin responsive gene expression is linked to hypocotyl growth. To functionally validate proteomic studies, a reverse genetics screen was performed on mutants in auxin‐regulated proteins to identify novel regulators of plant growth. This uncovered a long hypocotyl mutant, which we called
- PAR ID:
- 10450812
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Plant Direct
- Volume:
- 5
- Issue:
- 6
- ISSN:
- 2475-4455
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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PHYTOCHROME INTERACTING FACTOR proteins and subsequent induction ofYUCCA auxin biosynthetic genes. To investigate the role ofYUCCA genes in phytochrome-mediated elongation, we examined auxin signaling kinetics after an end-of-day far-red (EOD-FR) light treatment, and found that an auxin responsive reporter is rapidly induced within 2 hours of far-red exposure.YUCCA2, 5, 8, and9 are all induced with similar kinetics suggesting that theycould act redundantly to control shade-mediated elongation. To test this hypothesis we constructed a yucca2, 5, 8, 9 quadruple mutant and found that the hypocotyl and petiole EOD-FR and shade avoidance responses are completely disrupted. This work shows thatYUCCA auxin biosynthetic genes are essential for detectable shade avoidance and thatYUCCA genes are important for petiole shade avoidance. -
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