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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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Experimental measurement and computational prediction of bacterial Hanks‐type Ser/Thr signaling system regulatory targets
Abstract Bacteria possess diverse classes of signaling systems that they use to sense and respond to their environments and execute properly timed developmental transitions. One widespread and evolutionarily ancient class of signaling systems are the Hanks‐type Ser/Thr kinases, also sometimes termed “eukaryotic‐like” due to their homology with eukaryotic kinases. In diverse bacterial species, these signaling systems function as critical regulators of general cellular processes such as metabolism, growth and division, developmental transitions such as sporulation, biofilm formation, and virulence, as well as antibiotic tolerance. This multifaceted regulation is due to the ability of a single Hanks‐type Ser/Thr kinase to post‐translationally modify the activity of multiple proteins, resulting in the coordinated regulation of diverse cellular pathways. However, in part due to their deep integration with cellular physiology, to date, we have a relatively limited understanding of the timing, regulatory hierarchy, the complete list of targets of a given kinase, as well as the potential regulatory overlap between the often multiple kinases present in a single organism. In this review, we discuss experimental methods and curated datasets aimed at elucidating the targets of these signaling pathways and approaches for using these datasets to develop computational models for quantitative predictions of target motifs. We emphasize novel approaches and opportunities for collecting data suitable for the creation of new predictive computational models applicable to diverse species.
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- Award ID(s):
- 1946944
- PAR ID:
- 10493790
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Molecular Microbiology
- ISSN:
- 0950-382X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1111/mmi.15220
