Aarhus Universitet

Lene Heegaard Madsen

Jens Stougaard Jensen

Elena Simona Radutoiu

Leila Tirichine

Niels Sandal

Esben Bjorn Madsen

Niels Norgaard Sandel

Kasper Røjkjær Andersen

Zoltan Bozsoki

Simon Boje Hansen

Kira Gysel

Niels Nørgaard Sandal

Aspects of the present disclosure relates to genetically altered LysM receptors. In particular, the present disclosure relates to a hydrophobic patch into the LysM2 domain which can increase affinity and/or selectivity for LCOs and by replacement of regions in the LysM1 domain with the corresponding regions of the LysM1 domain from a donor LysM receptor that can alter the affinity and/or selectivity for the oligosaccharide particularly for LCOs and can alter the specificity between LCO when using regions from a high affinity and specificity LCO LysM receptor such as a legume NFR1 receptor. The present disclosure also relates to genetically altering LysM receptors in plants to include a hydrophobic patch or alter the hydrophobic patch and to genetically altering LysM receptors in plants by replacement of regions in the LysM2 domain.

Genetically altered LysM receptors with altered agonist specificity and affinity

Formation of nitrogen fixing root nodules in legumes is induced by perception of lipochitin-oligosaccharide signal molecules secreted by compatiblebacteria, which triggers a common symbiotic pathway. The present invention provides a spontaneous nodule formation (snf1-5g) mutant, in which the formation of symbiotic nodules is deregulated, leading to nodule development in the absence as well as in the presence ofbacteria and/or exogenous rhizobial signals. The invention further provides an isolated DNA sequence encoding a mutant chimeric Ca/calmodulin dependent protein kinase whose activity results in this &grave;gain of function' phenotype of spontaneous nodule formation. Furthermore the snf1-5g gene is shown to confer a spontaneous nodule formation phenotype to plants having a nodulation deficient genetic background. A gene of the invention, that confers a spontaneous nodulation phenotype, has utility for the transfer and establishment of nitrogen fixing capability in non-nodulating plants, and thereby reducing the nitrogen fertilizer dependence of non-nodulating crop plants.

Spontaneous nodulation in plants

The present invention provides a Nod-factor binding element, comprising one or more NFR polypeptides encoded by NFR genes, that are useful for providing non-nodulating plants with Nod-factor binding properties and triggering the endosymbiotic signalling pathway leading to nodulation. Furthermore the invention is useful for breeding for improved nodulation in nodulating legumes.

Nod-factor perception

Growing community of inventors

Risskov, Denmark

Lene Heegaard Madsen