Quantitative imaging reveals the role of MpARF proteasomal degradation during gemma germination

Das, Shubhajit; de Roij, Martijn; Bellows, Simon; Alvarez, Melissa Dipp; Mutte, Sumanth; Kohlen, Wouter; Farcot, Etienne; Weijers, Dolf; Borst, Jan Willem

Abstract

The auxin signaling molecule controls a variety of growth and developmental processes in land plants. Auxin regulates gene expression through a nuclear auxin signaling pathway (NAP) consisting of the ubiquitin ligase auxin receptor TIR1/AFB, its Aux/IAA degradation substrate, and DNA-binding ARF transcription factors. Although extensive qualitative understanding of the pathway and its interactions has been obtained, mostly by studying the flowering plant Arabidopsis thaliana, it remains unknown how these translate to quantitative system behavior in vivo, a problem that is confounded by the large NAP gene families in most species. Here, we used the minimal NAP of the liverwort Marchantia polymorpha to quantitatively map NAP protein accumulation and dynamics in vivo through the use of knockin fluorescent fusion proteins. Beyond revealing the dynamic native accumulation profile of the entire NAP protein network, we discovered that the two central ARFs, MpARF1 and MpARF2, are proteasomally degraded. This auxin-independent degradation tunes ARF protein stoichiometry to favor gene activation, thereby reprogramming auxin response during the developmental progression. Thus, quantitative analysis of the entire NAP has enabled us to identify ARF degradation and the stoichiometries of activator and repressor ARFs as a potential mechanism for controlling gemma germination.

Citation

Das, S., de Roij, M., Bellows, S., Alvarez, M. D., Mutte, S., Kohlen, W., Farcot, E., Weijers, D., & Borst, J. W. (2024). Quantitative imaging reveals the role of MpARF proteasomal degradation during gemma germination. Plant Communications, 5(11), Article 101039. https://doi.org/10.1016/j.xplc.2024.101039

• Journal Article Type: Article
• Acceptance Date: Jul 8, 2024
• Online Publication Date: Jul 9, 2024
• Publication Date: Nov 11, 2024
• Deposit Date: Jul 11, 2024
• Publicly Available Date: Jul 11, 2024
• Electronic ISSN: 2590-3462
• Publisher: Elsevier (Cell Press)
• Peer Reviewed: Peer Reviewed
• Volume: 5
• Issue: 11
• Article Number: 101039
• DOI: https://doi.org/10.1016/j.xplc.2024.101039
• Public URL: https://nottingham-repository.worktribe.com/output/37153091
• Publisher URL: https://www.cell.com/plant-communications/fulltext/S2590-3462(24)00380-8
• Related Public URLs: https://www.sciencedirect.com/science/article/pii/S2590346224003808