Legume and rhizobia symbiosis plays an important role in conversion of atmospheric dinitrogen to ammonia. On a global scale, this interaction represents a key entry point for reduced nitrogen into the biosphere, and as a consequence this symbiosis is important in both natural and agricultural systems. Symbiotic development of nodule organ is triggered by chito-oligosaccharide signals (Nod factors) from the bacterium which are perceived by the legume root. Understanding the molecular and cellular processes that underlie Nod factor perception is one focus of legume biology. Although forward genetics has proved to be an important tool to identify key players in Nod factor perception, we still know relatively little regarding the functional networks of genes and proteins that connect the earliest steps of Nod factor perception to immediate downstream outcomes. To elucidate genes and proteins that link Nod factor perception to cellular and physiological responses we are taking a discovery-based strategy based on whole transcriptome profiling using RNA-seq analysis in the roots of Medicago truncatula in response to Sinorhizobium meliloti. Functional characterization of a number of candidate genes is currently in progress to further examine their role in nodulation such as generating transgenic plants

Legume and rhizobia symbiosis plays an important role in conversion of atmospheric dinitrogen to ammonia. On a global scale, thin interaction represent a key entry point for reduced nitrogen into the biosphere, and as a consequence this symbiosis in important in both natural and agricultural systems. Symbiotic development of nodule organ in triggered by chito-oligosaccharide signals(Nod factors) from the bacterium which are perceived by the legume root. Understanding the molecular and cellular processes that underlie Nod factor perception is one focus of legume biology. Although forward genetics has proved to be an important tool to elucidate key players in Nod factor perception, we still know relatively little regarding the functional networks of genes and proteins that connect the earliest steps of Nod factor perception to immediate downstream outcomes. To identify genes and proteins that link Nod factor perception to cellular and physiological responses we are taking a discovery-based strategy on large-scale transcriptome profiling using RNA sequencing in the roots of Medicago truncatula in response to Sinorhizobium meliloti. Functional characterization of a number of candidate genes is currently in progress to further examine their role in nodulation.