First evidence of the activation of Cg-timp, an immune response component of pacific oysters, through a damage-associated molecular pattern pathway

Abstract

In a previous work, we characterized a Crassostrea gigas cDNA (Cg-timp) encoding a protein which presents all the features of vertebrate tissue inhibitor of metalloproteinase (TIMP). The expression pattern of this gene led us to propose that Cg-timp is an important factor in oyster wound healing and defense mechanisms. Here we describe the analysis of Cg-timp expression in oysters challenged by live or dead bacteria as well as by bacterial secretory/excretory products and metalloproteinase. Surprisingly, bacterial secretory/excretory products activate Cg-timp gene expression whereas heat-inactivated ones do not. To address the question of the signal transduction pathway involved in Cg-timp gene activation, we isolated and sequenced Cg-timp promoter and upstream region. A 1-kb genomic DNA fragment flanking the 5'-end of the gene contains several regulatory elements and notably three NF-kappaB binding sites. The potential involvement of these motifs in Cg-timp gene regulation is discussed.

Age-dependent expression of stress and antimicrobial genes in the hemocytes and siphon tissue of the Antarctic bivalve, Laternula elliptica, exposed to injury and starvation

“…In C. gigas, TIMP-like molecules were shown to be upregulated in response to shell damage or infection with Vibrio spp. (Montagnani et al 2001(Montagnani et al , 2007. However, De Decker and Saulnier (2011) as well as Labreuche et al (2006) found strong downregulation or no response to Vibrio spp.…”

Genomic Approaches in Aquaculture and Fisheries

“…PAMPs are exclusive to microbes and are not produced by hosts, emerging as indispensable for microbial fitness (Nürnberger et al 2004). Nevertheless, activation of defence mechanisms in oyster species could be triggered not only by PAMPs but also by damage-associated molecular patterns (DAMPs), as defined in the Matzinger damage model , Matzinger 2002, Montagnani et al 2007). Host molecules recognizing PAMPs are called Pattern Recognition Molecules (PRM) or Pattern Recognition Receptors (PRR; .…”

The Effects of 4-Nonylphenol on the Immune Response of The Pacific Oyster, Crassostrea Gigas, Following Bacterial Infection (Vibrio Campbellii)

“…In C. gigas, Cg-timp is thought to be involved in host immune reactions and tissue repair (Montagnani et al, 2007). In all three tissues tested, we saw a general decrease in Cg-timp transcript abundance in response to bacterial exposure, but only expression changes in gill tissue exhibited a significant decrease (Fig.…”

“…However, subsequent work suggested that Cg-timp activation in response to infection is independent of a non-self recognition step and its precise role in responding to bacterial infection is unknown (Montagnani et al, 2007).…”

“…In response to contamination, host defense mechanisms in C. gigas are triggered in three essential steps: detection of infecting microorganisms, activation of intracellular signaling pathways, and triggering of effector mechanisms (Montagnani et al, 2007). Subsequent to exposure, oysters mount two-fold defense mechanisms encompassed by cellular and humoral components that work in concert to recognize and eliminate pathogens.…”