Comparative genomic and transcriptomic analyses of legume genes controlling the nodulation process

Abstract

The availability of essential nutrients such as nitrogen (N) is often a limitation to plant development. In order to overcome this constraint, several plant species develop a mutualistic symbiotic relationship with actinorhizal bacteria (e.g. Frankia) and proteobacteria (e.g. Rhizobia) which are able to fix and assimilate the atmospheric nitrogen for their host plant. This symbiosis also named nodulation has been extensively analyzed during the past decades across several members of the Leguminosae family. Specifically, upon development of forward and reverse genetic tools, legume genes acting as key regulators of the nodulation process have been characterized. In this book chapter, upon describing legume nodule organogenesis, we will focus on the advantages of comparative transcriptomic analysis to reveal the levels of conservation and divergence of the regulatory genes and pathways controlling the early and late stages of the nodulation process between different legumes species.