The molecular mechanisms of quantitative resistance (QR) to fungal pathogens and their relationships with growth pathways are poorly understood. We identified tomato TRK1 (TPK1b Related Kinase1) and determined its functions in tomato QR and plant growth. TRK1 is a receptor‐like cytoplasmic kinase that complexes with tomato LysM Receptor Kinase (SlLYK1). Further, TRK1 is also required for maintenance of proper meristem growth, as revealed by the ectopic meristematic activity, enhanced branching, and altered floral structures in Overall, through molecular and biochemical interactions with critical regulators, TRK1 links upstream defense and growth signals to downstream factor in fungal resistance and growth homeostasis response regulators.
Vascular stem cell maintenance is regulated by a peptide signaling involving Tracheary Element Differentiation Inhibitory Factor (TDIF) and Receptor TDR/PXY (Phloem intercalated with Xylem) and co‐receptor BAK1 (BRI1‐associated receptor kinase1). The regulatory mechanism of this signaling pathway is largely unknown despite its importance in stem cell maintenance in the vascular meristem. We report that activation of a NAC domain transcription factor XVP leads to precocious Xylem differentiation, disruption of Vascular Patterning, and reduced cell numbers in vascular bundles. We combined molecular and genetic studies to elucidate the biological functions of XVP. XVP is expressed in the cambium, localized on the plasma membrane and forms a complex with TDIF co‐receptors PXY‐BAK1. Simultaneous mutation of Therefore, XVP functions as a negative regulator of the TDIF‐PXY module and fine‐tunes TDIF signaling in vascular development. These results shed new light on the mechanism of vascular stem cell maintenance.
- NSF-PAR ID:
- 10455349
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 226
- Issue:
- 1
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 59-74
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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