Location: Physiology and Pathology of Tree Fruits Research
Title: Direct attenuation of Arabidopsis ERECTA signalling by a pair of U-box E3 ligasesAuthor
CHEN, LIANGLIANG - University Of Texas At Austin | |
COCHRAN, ALICIA - University Of Texas At Austin | |
Waite, Jessica | |
SHIRASU, KEN - Riken Institute | |
BEMIS, S - University Of Washington | |
TORII, KEIKO - University Of Texas At Austin |
Submitted to: Nature Plants
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/28/2022 Publication Date: 12/20/2022 Citation: Chen, L., Cochran, A.M., Waite, J.M., Shirasu, K., Bemis, S.M., Torii, K.U. 2022. Direct attenuation of Arabidopsis ERECTA signalling by a pair of U-box E3 ligases. Nature Plants. 9:112-127. https://doi.org/10.1038/s41477-022-01303-x. DOI: https://doi.org/10.1038/s41477-022-01303-x Interpretive Summary: A great deal of plant development and response to the environment happens because receptors on the surface of cells receive and send signals to and from neighboring cells and the surrounding environment. It is important that these signals are turned on and off at the correct time, so that plants develop and respond when they are supposed to. This work reveals how cell signals for plant organ elongation (and thus overall plant architecture) and patterning of the epidermis are turned off properly. The ERECTA protein is a Receptor Kinase that is important for the proper length of inflorescence stems and development of stomata, the cells on the plant surface that allow gas exchange. This study describes two proteins, PLANT U-BOX (PUB)30 and PUB31, and the role they play in targeting ERECTA proteins to be recycled, allowing for normal architecture and stomatal development. Technical Abstract: Plants sense a myriad of signals through cell-surface receptors to coordinate their development and environmental response. The Arabidopsis ERECTA receptor kinase regulates diverse developmental processes via perceiving multiple EPIDERMAL PATTERNING FACTOR (EPF)/EPF-LIKE peptide ligands. How the activated ERECTA protein is turned over is unknown. Here we identify two closely-related Plant U-box ubiquitin E3 ligases, PUB30 and PUB31, as key attenuators of ERECTA signaling for two distinct developmental processes: inflorescence/pedicel growth and stomatal development. Loss-of-function pub30 pub31 mutant plants exhibit extreme inflorescence/pedicel elongation and reduced stomatal numbers owing to excessive ERECTA protein accumulation. Ligand-activation of ERECTA leads to phosphorylation of PUB30/31 by the co-receptor BRI1 ASSOCITED KINASE1 (BAK1), which then promotes PUB30/31 to associate with and ubiquitinate ERECTA for eventual degradation. We further show that both PUB30 and PUB31 phosphorylation and their ubiquitination activities are critical for the proper in vivo developmental outputs. Our work highlights PUB30 and PUB31 as integral components of the ERECTA regulatory circuit that ensures optimal signaling strengths upon ligand activation, thereby enabling proper growth and development. |