The activities of the coiled coil (CC), nucleotide-binding (NB), leucine-rich repeat (LRR) resistance protein Gpa2 from potato and its close homolog Rx1 are regulated by interdependent interactions of the LRR and CC with the NB domain. Both proteins require a nucleocytoplasmic distribution in the cell for proper functioning. Their CC influences this distribution by association with either nuclear components or with the cytoplasmic co-factor RanGTPase Activating Protein 2 (RanGAP2) which retains the proteins in the cytoplasm. This study is focused on the role of the CC and its interaction with RanGAP2 in the regulation of activation of resistance and cell death responses. Intra- and intermolecular interactions of the R protein have been visualised using Fluorescence Lifetime Imaging Microscopy. Aside from the EDVID motif a few aromatic residues in the N-terminal half of the CC are required for the interaction of the CC with the NB-LRR, but not RanGAP2. Mutations in one region of the CC affect cell death more than resistance signaling, suggesting that the CC plays different roles in regulating either pathway. In addition, mutations in the CC affect the nucleocytoplasmic distribution, underscoring the close link between protein structure, complex formation and subcellular localisation. Disruption of the structure of the CC leads to a more cytoplasmic localisation whereas mutants affected in their interaction with RanGAP2 are no longer sequestered in the cytoplasm by RanGAP2.
|Publication status||Published - 2 Mar 2017|
|Event||4th Annual Conference of the COST Action - Bled, Slovenia|
Duration: 1 Mar 2017 → 3 Mar 2017
|Conference||4th Annual Conference of the COST Action|
|Period||1/03/17 → 3/03/17|
Slootweg, E. J., Pomp, H., Roosien, J., Voogt, L., Sukarta, O. C. A., & Goverse, A. (2017). Inter- and intramolecular interactions regulating the activity of the CNL immune receptors Rx1 and Gpa2 in complex with RanGAP2. 27. Abstract from 4th Annual Conference of the COST Action, Bled, Slovenia.