Ramya Ganesan

 

Research Interests

Topic
Molecular basis of host-symbiont interactions in the defensive symbiosis between Lagria beetles and Burkholderia bacteria.

I study the molecular mechanisms of host- bacterial interactions using the Lagria- Burkholderia defensive symbiosis as a model system. Female Lagria beetles harbour bacterial symbionts, Burkholderia gladioli, in the accessory glands of their reproductive system. They deposit B. gladioli on the egg surface during oviposition where the bacteria produce a combination of bioactive agents that prevent the growth of pathogenic fungi. At least three B. gladioli strains are associated to a single beetle host, yet the mechanisms for selecting and maintaining multiple strains are unknown. Furthermore, despite their mutualistic life-style in a beetle, the B. gladioli symbionts have the capability to infect and negatively affect a plant host.

Illustration: Lagria villosa on a soybean leaf - RG

Many questions remain unanswered about the molecular interactions of the Lagria- Burkholderia symbiosis. During the establishment of symbiosis, bacteria must communicate with the host and possibly with other strains present in the same host. Microbial communication mechanisms are likely to be involved in these interactions. The host in turn is expected to use innate immune factors that control and maintain its symbionts. Using molecular biology methods and genetic manipulation, I aim to identify which colonization factors are involved when B. gladioli initiate the symbiosis. I am also using molecular biology methods to study the beetles’ immune response to their symbiotic partners.