Molecular Signatures of Nicotinoid-Pathogen Synergy in the Termite Gut

• DOI: 10.1371/journal.pone.0123391
• Publication Date: 2015-04-02T18:01:00Z
• Authors: Ruchira Sen; Rhitoban Raychoud...; Yunpeng Cai; Yijun Sun; Verena-Ulrike Lietze; Brittany F. Peterson; Michael E. Scharf; Drion G. Boucias
• Keywords: Protist; Reticulitermes

Previous studies in lower termites revealed unexpected synergies between nicotinoid insecticides and fungal entomopathogens. The present study investigated molecular mechanisms of nicotinoid-pathogen synergy the termite Reticulitermes flavipes, using nicotinoid, imidacloprid, combination with bacterial Particular focus was placed on metatranscriptome composition microbial dynamics symbiont-rich gut, which houses diverse mixes protists bacteria. cDNA microarrays containing a mix host protist symbiont oligonucleotides were used to simultaneously assess gene expression. Five treatments compared that included single challenges sublethal doses fungi (Metharizium anisopliae), bacteria (Serratia marcescens) or dual + imidacloprid imidacloprid. Our findings point towards dysbiosis compromised social behavior, rather than suppression stereotypical immune defense mechanisms, as dominant factors underlying termites. Also, greater impacts observed for pathogen suggest rich community R. flavipes gut (>5000 species-level phylotypes) exists an ecological balance effectively excludes exogenous pathogens. These significantly advance our understanding antimicrobial defenses this important eusocial insect group, well provide novel insights into how nicotinoids can exert deleterious effects colonies.