In-silico identification of Medicago truncatula genes involved in purine transport and metabolism

Abstract

Leguminous plants grow on nitrogen-limited soils based on their symbiosis with rhizobial nitrogen-fixing bacteria. This symbiosis provides the majority of biologically available nitrogen for cycling in the biosphere and serves as an important natural fertilizer in agricultural systems by allowing natural enrichment of soils with nitrogen. In consequence, leguminous plants are a crucial part of the human diet and of animal feeds and their optimal growth is of major economical and agricultural importance. Better knowledge on the genetic and metabolic regulation of symbiotic nitrogen fixation, can be implemented for improvements on the efficiency of such systems in the field. For this purpose, a bioinformatics approach was undertaken to study purine transport and metabolism, an aspect not studied in the past. Several Medicago truncatula genes involved in purine transport and metabolism were identified including the nodulespecific purine permease Pup1 and the nodule-induced genes coding for adenine phosphoribosyltransferase-like protein (APT1), adenosine/AMP deaminase (AMPD), inosine-uridine preferring nucleoside hydrolase (IUNH5) and nucleobase-ascorbate transporter-like protein (NAT14).