Regulation of root attachment in Rhizobium - AfS, ENWW

The attachment to legume roots of soil rhizobia represents the first key stage of physical interaction between host plants and future endosymbionts in nitrogen fixing Rhizobiumlegume symbioses. It is these symbioses that give the plants a 'self-fertilizing' phenotype, and can largely free them from synthetic fertilizer requirements. This is important, as synthetic fertilizers are both expensive and environmentally polluting. Complex genetic switches, controlled in a precise spatio-temporal fashion, are required to enable the appropriate activation of root attachment factors in both the eukaryote and prokaryotes. The production by Rhizobium of exopolysaccharide (EPS) is particularly important for this interaction. Previous work has identified a sigma factor (EcfE) in Rhizobium leguminosarum biovar viciae 3841, which acts as a master regulator of pea root attachment, as well as a diguanylate cyclase (RL2880) important for EPS production. Building on these findings, this work aims to expand knowledge of the genetic regulation surrounding root attachment, using mutagenesis screens and other in vitro techniques to reveal new regulatory hierarchies. It is hoped that a greater understanding of this area may contribute to enhancing the efficiency of these symbioses, or even transferring them to non-legume plants, thereby contributing to sustainability in agriculture as well as global food security.

BBSRC priority areas addressed by this research -
Food, Nutrition and Health
Sustainably Enhancing Agricultural Production
Synthetic Biology
Global Food Security