Inhibition of rhizobial cheaters by the host Medicago truncatula involves repression of symbiotic functions and induction of defense.

ABSTRACT: In symbiotic plant-microbe interactions, the host invests considerable amounts of resources in the microbial partner. If the microbe does not reciprocate with a comparable symbiotic benefit, it is regarded as a cheater. The host responds to cheaters with negative feedback mechanisms (sanctions) to prevent fitness deficits resulting from being exploited. We study sanctioning in the symbiosis between Medicago truncatula and the nitrogen-fixing rhizobium Sinorhizobium meliloti. We manipulated the exchange of resources between the partners in three ways: by using mutant rhizobia defective in nitrogenase; replacing nitrogen in the atmosphere with argon gas; and supplying rich nitrogen fertilizer to the host. We follow the consequences of simulated cheating by examining the metabolome and proteo

SUBMITTER: Chen M 

PROVIDER: S-EPMC12489286 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature