Plant Signaling: Brassinosteroids, Immunity and Effectors Are BAK !

Bacterial effectors target the common signaling partner BAK1 to disrupt multiple MAMP receptor-signaling complexes and impede plant immunity.

Successful pathogens have evolved strategies to interfere with host immune systems. For example, the ubiquitous plant pathogen Pseudomonas syringae injects two sequence-distinct effectors, AvrPto and AvrPtoB, to intercept convergent innate immune responses stimulated by multiple microbe-associated molecular patterns (MAMPs). However, the direct host targets and precise molecular mechanisms of b...

Bacterial Effectors Target BAK1 to Disrupt MAMP Receptor-Signaling Complexes and Impede Plant Innate Immunity

Brassinosteroids inhibit pathogen-associated molecular pattern-triggered immune signaling independent of the receptor kinase BAK1.

Plants and animals use innate immunity as a first defense against pathogens, a costly yet necessary tradeoff between growth and immunity. In Arabidopsis, the regulatory leucine-rich repeat receptor-like kinase (LRR-RLK) BAK1 combines with the LRR-RLKs FLS2 and EFR in pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and the LRR-RLK BRI1 in brassinosteroid (BR)-mediated growt...

IN THIS ISSUE Brassinosteroid Perception and Signaling: Heterodimerization and Phosphorylation of Receptor-Like Kinases BRI1 and BAK1

Brassinosteroids (BRs) are plant growth hormones that are structurally similar to insect and animal steroids. Since the discovery of BRs in Brassica napus pollen, more than 40 BR-like compounds have been identified in numerous plant species (Altmann, 1999). BRs show a strong growth-promoting effect when applied to plants in nanomolar concentrations because of positive effects on both cell divis...

Multiple mechanisms modulate brassinosteroid signaling.

Brassinosteroids are essential hormones for plant growth and development. Genetic studies have identified key components of the BR signaling pathway, including the cell-surface receptor kinases that perceive BR, an intracellular kinase and a phosphatase, and nuclear transcription factors. Subsequent biochemical studies have revealed many details about signaling events from BR perception at the ...