664 / 2019-04-30 12:13:45

Functional analysis of the Arabidopsis non-characterized Leucine-rich receptor-like kinase, LRR2, interacting with defence-related G-proteins

Arabidopsis, receptor-like kinase, LRR2, plant immunity, G-proteins, F. oxysporum, A. brassicicola, P. syringae, Callose deposition.

全体主题 > Signal Transduction

The first step in plant immunity is the recognition of potential pathogens by receptors located on the cell surface that mostly belong to the receptor-like kinase (RLK) family. The largest subgroup of this family is the Leucine-rich receptor-RLK (LRR-RLK). heterotrimeric G proteins (G proteins) are conserved multifunctional signalling elements in Eukaryotes with an active role in the plant immune response. G proteins consist of three distinct subunits Gα, Gβ and Gγ. Upon activation, Gα and the Gβγ dimer independently trigger multiple downstream effectors mediating specific signal pathways. We have performed the initial characterization of LRR2, a LRR-RLK showing physical interaction with G proteins as well as other defence related proteins.
The lrr2 single mutant showed enhanced resistance to Fusarium oxysporum, however, it exhibited similar responses as wild-type to Alternaria brassicicola, and Pseudomonas syringae pv. tomato DC3000. The double lrr2 agb1 mutant showed increased sensitivity to F. oxysporum compared to WT, but identical sensitivity levels than the single agb1 mutant, suggesting that LRR2 and AGB1 might signal in the same defence pathway. In addition, we found that lrr2 mutant displayed reduced callose deposition in response to flg22 compared with WT. These results suggested that LRR2 might trigger multiple pathways in Arabidopsis defence. The functional characterization of LRR2 is valuable to understand the involvement of RLKs in plant immunity.