University of Warwick: International collaboration identifies crop resistance targets

An international study has identified molecules that could prove key targets in crop resistance. Globally, pests and pathogens amount to more than 30% of crop losses, posing a huge threat to food production. In response to this threat, scientists have identified and classified new isomers (different variants of molecules) that could help develop more robust and resistant crops – via synthetic biology approaches. Using structural biology, modelling and functional studies, leading scientists characterised new isomers present in both bacteria and plants. The study was funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and involved collaboration between the University of Warwick, and universities in Australia (University of Queensland, Griffith University) and America (University of Nebraska, Washington University). The isomers are variants of a well-known signalling molecule, cyclic ADP ribose (cADPR), which is formed via enzymatic activity of a protein domain, Toll Interleukin 1 Receptor (TIR). It was discovered that TIRs produce different variants of cADPRs (v-cADPRs), and that these isomers have different influences on bacterial and plant immunity. The bacterial TIR isomer, 3’v-cADPR, was shown not only to activate bacterial immunity, but to also help suppress plant immune responses, which could lead to crop losses. By contrast, the plant isomer 2’v-cADPR contributes to fending off plant pathogens, such as bacteria, fungi and oomycetes. The real-world application of this study is not to be understated, as it was the first identification of the structure of these new compounds, it provides the opportunity of developing more robust crops using synthetic biology approaches. This offers new approaches and targets in the field of crop resistance. Professor Murray Grant, Preofessor of xx at Warwick University commented “It’s been a privilege to work with such a talented international team on this piece of work, and we are very grateful for the funding received by BBSRC. “The results were quite unexpected; we didn’t expect the TIR isomers to have such contrasting roles in immunity responses of plants and bacteria. It was exciting to discover these novel molecules. “More research is required to understand what extent 2’v-cADPR and 3’v-cADPR function in plant disease and defence responses. That would be another beneficial step in helping to develop pathogen-resistant crops around the world.”