How plants recognize nematodes: Signal and signalling

• Applicant: Professor Dr. Florian M. W. Grundler, since 3/2019
• Subject Area: Plant Breeding and Plant Pathology
• Term: from 2016 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 322151769

Plant parasitic nematodes are obligate biotrophs that feed exclusively from host tissues. A plant invasion by nematodes may activate the hosts immune system through recognition of pathogen associated molecular patterns (PAMPs) or damage associated molecular patterns (DAMPs). Plants possess surface localized receptors (PRRs) that monitor for the presence of PAMPs or DAMPS and initiate immune responses upon detection. There are well characterized examples of PAMPs and perceiving receptors for bacterial, fungal and insect pathogens in plants. However, little is known about surface recognition of parasitic nematodes in plants. Here we showed that a nematode aqueous diffusate (NemaWater) contain proteinaceous elicitor(s) capable of inducing PTI in Arabidopsis in a manner dependent on the common immune co-receptor BAK1. The results showed that a leucine-rich repeat receptor-like kinase, termed NILR1, is essential for the induction of immune responses by NemaWater and for immunity to nematodes. Treatment of plants with NemaWater induces ROS-burst, one of the hallmark responses of PTI and inhibition of growth in Wild-type Arabidopsis plants but not in plants carrying loss-of-function mutations in NILR1 gene. NILR1 knock out mutants were more susceptible to a broad range of nematodes as compared with wild-type control plants. The first objective of the current project is to isolate the elicitor fraction in NemaWater and purify it to a degree that ensures the presence of a single type of NAMP in the elicitor fraction. This will be followed by a series of experiments characterising isolated NAMP for its PTI eliciting capacity. The second objective of the project is to characterise NILR1 in greater detail for its role in surface perception during plant-nematode interaction. Furthermore, NILR1 mediated signalling pathways activated upon NemaWater treatment or nematode infection will be dissected in details.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr. Shahid Siddique, until 2/2019