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Abstract RAF-like kinases, members of the mitogen-activated protein kinase kinase kinase (MAPKKK) family, are central integrators of external and internal signals in plant stress responses and growth regulation. These kinases mediate signaling through multiple hormone pathways, including abscisic acid-dependent and -independent pathways, ethylene signaling, and rapid auxin responses. Unlike typical MAPKKKs that function through kinase cascades, RAF-like kinases primarily employ direct phosphorylation of downstream targets and dynamic subcellular localization to mediate specific physiological responses. Here, we review the emerging roles of RAF-like kinases in Arabidopsis thaliana, highlighting their integrative functions in hormone signaling, stress responses, and growth control. The complex interplay between different RAF-like kinase subgroups and their diverse cellular targets underscores the intricate regulatory mechanisms plants have evolved to coordinate environmental responses with development.
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DNA-encoded probe-based assay for profiling plant kinase activities
Abstract Elucidating kinase–substrate relationships is pivotal for deciphering cellular signaling mechanisms, yet it remains challenging due to the complexity of kinase networks. Herein, we report the development of a versatile DNA-based kinase assay platform for high-throughput profiling of plant protein kinase activities and substrate preferences. Our approach employs DNA-linked peptide substrates, facilitating quantitative and specific kinase activity detection through next-generation DNA sequencing. Leveraging DNA barcodes as quantitative readouts, our approach establishes a high-throughput, sensitive, and specific platform for dissecting kinase–substrate networks in plants, representing a powerful tool for elucidating signaling mechanisms in plants.
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- PAR ID:
- 10525980
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- PNAS Nexus
- Volume:
- 3
- Issue:
- 7
- ISSN:
- 2752-6542
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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