Meeting Abstract
31.2 Monday, Jan. 5 Form and function of a novel metalloproteinase from the Eastern Oyster, Crassostrea virginica PROESTOU, DA*; SALGER, S; VAUGHN, C; GOMEZ-CHIARRI, M; University of Rhode Island dpro1791@postoffice.uri.edu
Among vertebrates, matrix metalloproteinases (MMPs) are a well-studied family of enzymes. They are zinc-dependent, degrade the extracellular matrix, and play a critical role in many physiological processes. MMPs have been isolated in only a handful of invertebrates and little is known about how they function. We have characterized a novel gene, Cv1MMP, in Crassostrea virginica. The goal of our research was to determine the key roles of this newly-identified oyster protein. We took a comparative approach by performing genomic analysis of MMPs across taxa, visualizing temporal and tissue-specific patterns of MMP production using immunofluorescence techniques, and evaluating protein activity in response to a variety of stimuli. The production of Cv1MMP is limited to few cell types, specifically blood and epithelial cells. Cv1MMP labeling was observed in hemocytes, the mantle, and digestive tract. An analysis of digestive tissue at multiple time points during feeding suggests that Cv1MMP production peaks between 10 and 90 minutes post ingestion of algae. Labeled hemocytes were seen migrating through the intestinal lumen. Cv1MMP was also localized in epithelial cells along the periostracal groove and middle lobe of the oyster mantle, which function in pathogen detection and shell formation. MMP activity was detected in oyster hemolymph and levels correlated to degree of infection by the protozoan parasite Perkinsus marinus. The presence of Cv1MMP in hemocytes and epithelial barrier tissues, as well as differential MMP activity in infected animals suggest a role for Cv1MMP in digestion, hemocyte migration, shell formation, and immune defense. By comparing the genomic structure, tissue patterns, activity and roles of Cv1MMP with those of MMPs from other taxa, we hope to gain insight to the evolution of function in this versatile family of genes.
