Role of Viruses in the Life Cycle and Endosymbiosis of a Sea Slug

University Of South Florida, Tampa FL

Investigators

Abstract

The digestive cells of the sea slug, Elysia chlorotica, have an endosymbiotic association with chloroplasts from the alga, Vaucheria litorea. These chloroplasts, obtained from ingested Vaucheria, remain viable and functioning within the sea slug for months. The PIs have previously demonstrated that the captive, functional plastids synthesize proteins, including those that seem to be coded for in the slug genome. They have recently identified some of those proteins as belonging to the light harvesting complex I (LHCI) and have developed preliminary molecular evidence for the presence of the LCHI gene in the slug genomic DNA. For this proof-of-concept award, the PIs will conduct experiments designed to identify plastid protein genes in the host cell genome. Such transfers of genes from the symbiont into the host cell nucleus must certainly have been associated with the mechanism of the widely accepted endosymbiotic origin of intracellular organelles, such as mitochondria and chloroplasts. If a successful interspecies gene transfer between an alga and a slug mediated by an endogenous virus can be demonstrated in the case of E. chlorotica, then an exemplary mechanism for this process will have been provided.