The potato cyst nematode resistance gene Gpa2 confers resistance to Globodera pallida. Gpa2 belongs to the class of CC-NB-LRR resistance genes and is located on a complex locus that also harbours the closely related Potato Virus X (PVX) resistance gene Rx1. Rx1 and Gpa2 are 88% identical at the amino acid level, yet they confer resistance to completely unrelated pathogens. For both R proteins, the pathogen elicitor that triggers the resistance response is known. Gpa2 recognizes the secreted Globodera pallida protein RBP1, whereas Rx1 detects the PVX coat protein. This makes Gpa2 and Rx1 an excellent model system to investigate how the recognition specificity is determined in NB-LRR proteins. To determine which amino acids may play a role in Gpa2 and Rx1 specificity, we combined sequence information of 35 closely related homologues derived from wild Solanum species, functional data and a consensus in sillico 3D model obtained in previous studies. For both Gpa2 and Rx1, two residues were detected which are located in the region that is crucial for elicitor recognition. In the 3D model, they map together on the LRR surface, suggesting a potential role in pathogen recognition. The functional validation of these residues is in progress.
|Title of host publication||The 31th International Symposium of the European Society of Nematologists, Adana, Turkey, 23-27 September 2012|
|Place of Publication||Adana, Turkey|
|Publication status||Published - 2012|
|Event||The 31th International Symposium of the European Society of Nematologists - Adana|
Duration: 23 Sep 2012 → 27 Sep 2012
|Conference||The 31th International Symposium of the European Society of Nematologists|
|Period||23/09/12 → 27/09/12|