Actin-bundling protein fimbrin serves as a new auxin biosynthesis orchestrator in Arabidopsis root tips.

Autor: Liu YK; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Li JJ; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Xue QQ; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Zhang SJ; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Xie M; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Cheng T; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Wang HL; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Liu CM; National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China., Chu JF; National Centre for Plant Gene Research (Beijing), Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.; College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, 100039, China., Pei YS; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Jia BQ; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Li J; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Tian LJ; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Fu AG; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Hao YQ; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China., Su H; Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, 710069, China.
Jazyk: angličtina
Zdroj: The New phytologist [New Phytol] 2024 Oct; Vol. 244 (2), pp. 496-510. Date of Electronic Publication: 2024 Jul 23.
DOI: 10.1111/nph.19959
Abstrakt: Plants delicately regulate endogenous auxin levels through the coordination of transport, biosynthesis, and inactivation, which is crucial for growth and development. While it is well-established that the actin cytoskeleton can regulate auxin levels by affecting polar transport, its potential role in auxin biosynthesis has remained largely unexplored. Using LC-MS/MS-based methods combined with fluorescent auxin marker detection, we observed a significant increase in root auxin levels upon deletion of the actin bundling proteins AtFIM4 and AtFIM5. Fluorescent observation, immunoblotting analysis, and biochemical approaches revealed that AtFIM4 and AtFIM5 affect the protein abundance of the key auxin synthesis enzyme YUC8 in roots. AtFIM4 and AtFIM5 regulate the auxin synthesis enzyme YUC8 at the protein level, with its degradation mediated by the 26S proteasome. This regulation modulates auxin synthesis and endogenous auxin levels in roots, consequently impacting root development. Based on these findings, we propose a molecular pathway centered on the 'actin cytoskeleton-26S proteasome-YUC8-auxin' axis that controls auxin levels. Our findings shed light on a new pathway through which plants regulate auxin synthesis. Moreover, this study illuminates a newfound role of the actin cytoskeleton in regulating plant growth and development, particularly through its involvement in maintaining protein homeostasis via the 26S proteasome.
(© 2024 The Author(s). New Phytologist © 2024 New Phytologist Foundation.)
Databáze: MEDLINE
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