Legume nodulation gene discovery

Abstract

Legumes enter a complicated symbiotic relation with Rhizobium bacterium to initiate a nitrogen fixing root nodule. The process is genetically and environmentally regulated. Our group researches the genetic components controlling nodule initiation and the regulation of nodule number (autoregulation). Several genes were cloned and characterised by either positional cloning, sequence homology, EST based screens, and fast neutron deletion mutagenesis. We find an abundance of receptor kinases, phosphatases and transcription factors as well as transporters involved in the symbiosis. Expression profiling by qRT-PCR and use of promoter fusions complement the initial stages of the analysis for interactions of the molecular components