Welcome to the Nishiguchi Lab
Research Interests: Evolution and marine symbiosis
Understanding the evolution of animal and bacterial associations has been an underlying theme in establishing the development and specificity of symbiotic relationships. There is a need to develop better systems to resolve interactions among symbiotic species where population dynamics and environmental processes clearly play an important role in the evolution of the association. These model systems should promote integrated approaches that take into account the response within as well as between various symbiotic populations and their host partners. My laboratory studies the mutualistic association between sepiolid squids (Mollusca: Cephalopoda) and their Vibrio symbionts which provides a versatile and experimentally tractable model system to study the population dynamics and cospeciation between bacterial species and their diversity among host squids.
Since the symbiotic bacteria are environmentally transmitted to new hosts with every generation, this system is ideal for the study of specificity amongst the wide variety of bacteria that reside in the water column. Moreover, it provides a system to resolve whether the ecology of the free-living symbiont is as important as the ecology of the mutualism in the architecture of bacterial-host interactions. My laboratory examines the mechanisms that drive host-symbiont recognition, and assesses whether environmental factors or inherent genetic characters affect speciation and diversity among Vibrio bacteria. Researchers in my laboratory focus on aspects of molecular signaling, population genetics of Vibrio bacteria, molecularspecificity of symbiosis genes, competitive exclusion of non-native symbionts, phylogenetic relationships among squids in thefamilySepiolidae, as well as modeling certain aspects of the ecology of the association.