Low Blue Light Enhances Phototropism by Releasing Cryptochrome1-Mediated Inhibition of PIF4 Expression.

Details

Serval ID
serval:BIB_FE090E44B17B
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Low Blue Light Enhances Phototropism by Releasing Cryptochrome1-Mediated Inhibition of PIF4 Expression.
Journal
Plant physiology
Author(s)
Boccaccini A., Legris M., Krahmer J., Allenbach-Petrolati L., Goyal A., Galvan-Ampudia C., Vernoux T., Karayekov E., Casal J.J., Fankhauser C.
ISSN
1532-2548 (Electronic)
ISSN-L
0032-0889
Publication state
Published
Issued date
08/2020
Peer-reviewed
Oui
Volume
183
Number
4
Pages
1780-1793
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Abstract
Shade-avoiding plants, including Arabidopsis (Arabidopsis thaliana), display a number of growth responses, such as elongation of stem-like structures and repositioning of leaves, elicited by shade cues, including a reduction in the blue and red portions of the solar spectrum and a low-red to far-red ratio. Shade also promotes phototropism of de-etiolated seedlings through repression of phytochrome B, presumably to enhance capture of unfiltered sunlight. Here we show that both low blue light and a low-red to far-red light ratio are required to rapidly enhance phototropism in Arabidopsis seedlings. However, prolonged low blue light treatments are sufficient to promote phototropism through reduced cryptochrome1 (cry1) activation. The enhanced phototropic response of cry1 mutants in the lab and in response to natural canopies depends on PHYTOCHROME INTERACTING FACTORs (PIFs). In favorable light conditions, cry1 limits the expression of PIF4, while in low blue light, PIF4 expression increases, which contributes to phototropic enhancement. The analysis of quantitative DII-Venus, an auxin signaling reporter, indicates that low blue light leads to enhanced auxin signaling in the hypocotyl and, upon phototropic stimulation, a steeper auxin signaling gradient across the hypocotyl. We conclude that phototropic enhancement by canopy shade results from the combined activities of phytochrome B and cry1 that converge on PIF regulation.
Pubmed
Web of science
Open Access
Yes
Create date
06/07/2020 12:53
Last modification date
15/09/2020 5:26
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