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Summary Plants have evolved a sophisticated immunity system for specific detection of pathogens and rapid induction of measured defences. Over‐ or constitutive activation of defences would negatively affect plant growth and development. Hence, the plant immune system is under tight positive and negative regulation. MAP kinase phosphatase1 (MKP1) has been identified as a negative regulator of plant immunity in model plantArabidopsis. However, the molecular mechanisms by which MKP1 regulates immune signalling in wheat (Triticum aestivum) are poorly understood. In this study, we investigated the role of TaMKP1 in wheat defence against two devastating fungal pathogens and determined its subcellular localization. We demonstrated that knock‐down ofTaMKP1by CRISPR/Cas9 in wheat resulted in enhanced resistance to rust caused byPuccinia striiformisf. sp.tritici(Pst) and powdery mildew caused byBlumeria graminisf. sp.tritici(Bgt), indicating thatTaMKP1negatively regulates disease resistance in wheat. Unexpectedly, whileTamkp1mutant plants showed increased resistance to the two tested fungal pathogens they also had higher yield compared with wild‐type control plants without infection. Our results suggested that TaMKP1 interacts directly with dephosphorylated and activated TaMPK3/4/6, and TaMPK4 interacts directly with TaPAL. Taken together, we demonstrated TaMKP1 exert negative modulating roles in the activation of TaMPK3/4/6, which are required for MAPK‐mediated defence signalling. This facilitates our understanding of the important roles of MAP kinase phosphatases and MAPK cascades in plant immunity and production, and provides germplasm resources for breeding for high resistance and high yield.
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This content will become publicly available on September 3, 2026
Diverse Functions of Plant MLO Proteins: From Mystery to Elucidation
Recessive mutations in the mildew locus O (MLO) gene were first identified as key factors conferring broad-spectrum resistance to powdery mildew in barley. This discovery inspired extensive research on MLOs and novel breeding strategies for powdery mildew resistance by targetingMLOgenes in various crops. Over the past two decades, studies have revealed broader roles for MLOs beyond powdery mildew susceptibility, including regulating interactions with diverse pathogens and symbionts, root thigmomorphogenesis, and reproductive development. Recent findings identify MLOs as calcium channels, offering a unifying molecular framework for understanding their diverse biological functions. However, significant challenges remain in comprehensively understanding the cellular and molecular mechanisms underlying MLO functions. In this review, we examine the MLO-related literature to delineate the multifaceted roles of MLOs in plant immunity and development. By integrating published phylogenetic, genetic, biochemical, and molecular studies with original in silico analyses, we propose mechanistic models to contextualize the diverse functions of MLOs with a focus on plant immunity and susceptibility.
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- PAR ID:
- 10656162
- Publisher / Repository:
- Annual Reviews
- Date Published:
- Journal Name:
- Annual Review of Phytopathology
- Volume:
- 63
- Issue:
- 1
- ISSN:
- 0066-4286
- Page Range / eLocation ID:
- 147 to 173
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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