Genetic analysis of the Arabidopsis TIR1/AFB auxin receptors reveals both overlapping and specialized functions
- University of California, San Diego, United States
- Salk Institute for Biological Sciences, United States
- University of Nottingham, United Kingdom
- Salk Institute for Biological Studies, United States
Abstract
The TIR1/AFB auxin co-receptors mediate diverse responses to the plant hormone auxin. The Arabidopsis genome encodes six TIR1/AFB proteins representing three of the four clades that were established prior to angiosperm radiation. To determine the role of these proteins in plant development we performed an extensive genetic analysis involving the generation and characterization of all possible multiply-mutant lines. We find that loss of all six TIR1/AFB proteins results in early embryo defects and eventually seed abortion, and yet a single wild-type allele of TIR1 or AFB2 is sufficient to support growth throughout development. Our analysis reveals extensive functional overlap between even the most distantly related TIR1/AFB genes except for AFB1. Surprisingly, AFB1 has a specialized function in rapid auxin-dependent inhibition of root growth and early phase of root gravitropism. This activity may be related to a difference in subcellular localization compared to the other members of the family.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figure 1-figure supplement 2B, Figure 1-figure supplement 4, Figure 1-figure supplement 5. Figure 5-figure supplement 1, Figure 6, Figure 6-figure supplement 2 , Figure 7, Figure 7-figure supplement 1
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One 1000 plant transciptomicshttps://datacommons.cyverse.org/browse/iplant/home/shared/commons_repo/curated/oneKP_capstone_2019.
Article and author information
Author details
Bipin Kumar Pandey
Rahul Arvind Bhosale
Funding
National Institutes of Health (GM43644)
- Mark Estelle
Human Frontier Science Program (LT000340/2019-L)
- Matthieu Platre
Biotechnology and Biological Sciences Research Council (research fellowship)
- Rahul Arvind Bhosale
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Prigge et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Genetic analysis of the Arabidopsis TIR1/AFB auxin receptors reveals both overlapping and specialized functions
eLife 9:e54740.
https://doi.org/10.7554/eLife.54740
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