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

海蛞蝓的消化细胞，Elysia chlorotica，具有与叶绿体的内共生协会，Vaucheria litorea。 这些叶绿体，从摄入的沃氏藻中获得，在海蛞蝓体内保持活力和功能数月。PI先前已经证明，捕获的功能质体合成蛋白质，包括那些似乎在蛞蝓基因组中编码的蛋白质。他们最近已经确定了其中一些蛋白质属于捕光复合物I（LHCI），并为蛞蝓基因组DNA中存在LCHI基因提供了初步的分子证据。对于这个概念验证奖，PI将进行旨在识别宿主细胞基因组中质体蛋白基因的实验。这种基因从共生体转移到宿主细胞核的过程，肯定与广泛接受的细胞内细胞器（如线粒体和叶绿体）的内共生起源机制有关。如果能在大肠杆菌和蛞蝓之间通过内源性病毒介导的成功的种间基因转移，chlorotica，则将提供该过程的示例性机制。

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.