In the immune response, a resistance protein from the host (R) recognizes an avirulent protein from the pathogen (Avr) and elicits a defence response that abrogates the infection attempt. The immune response is generally accompanied by the hypersensitive response (HR), a form of programmed cell death (PCD) that manifests within hours after R/Avr recognition. In a random Virus-Induced-Gene-Silencing (VIGS) screening of a Nicotiana benthamiana cDNA library, I identified several genes that participate in the HR. Among those genes, I characterized in detail a MAPK kinase kinase kinase (MAPKKKa), a positive regulator of cell death in inmunity and susceptibility. I also identified a calcineurin B-like protein (NbCBL) and its target, a CBL-interacting protein kinase (NbCIPK).
These results implicate for the first time members of the CBL and CIPK families in biotic stress signalling. As a short-term goal, this project will focus on the characterization of NbCBL and NbCIPK in the immune and susceptible responses to pathogens in Solanaceae and Arabidopsis. For this purpose, I will use functional, biochemical, sub-cellular localization and genetic approaches. I will also investigate if there is a connection between the phosphorylation cascades elicited by CBL-CIPK and MA PKKKa. As a mid-long term goal, I plan to establish an optimised Forward Functional Genomics Screening strategy aimed to the targeted identification of genes that participate in early signalling events in the immune response (between R/Avr and MAPKKKa).
Call for proposal
See other projects for this call