Full-length sequence and expression analysis of Toll-like receptor 9 in the gilthead seabream (Sparus aurata L.)

The expression profile of TLR9 mRNA and CpG ODNs immunostimulatory actions in the teleost gilthead seabream points to a major role of lymphocytes

“…Taking in consideration binding properties, immunostimulation effects, and scarce effect on TLR9 gene expression by synthetic ODNs, we were prompted to further investigate seabream TLR9 gene expression and regulation by real-time PCR. In agreement with previous data [18], TLR9 gene expression was evident in most tissues of resting seabream (Fig. 6a).…”

“…This important observation led us to evaluate the presence and regulation of TLR9 gene in an attempt to elucidate its involvement in leucocyte activation in seabream. In agreement with a previous study [18], gilthead seabream TLR9 is widely detected in most tissues with major transcript levels in PELs and PBLs. Furthermore, we used a combination of strategies based on plastic adherence, MACS and FACS to obtain highly pure Ly, MM and AG populations [25 -28].…”

“…In our group, moreover, incubation of purified AG or MM with several PAMPs, including bacterial DNA, showed that only MM were primed to increase TLR9 gene expression whilst both leucocyte populations were primed to increase phagocytic activity, ROI production, and expression of IL-1b, TNFa or COX-2 genes [32]. Although data are scarce in fish, TLR9 gene expression was only studied and increased in olive flounder and zebrafish challenged with Edwardsiella tarda or Mycobacterium maritinum, respectively [19,20] but reduced in seabream [18]. Further studies are mandatory to understand how the TLR9 gene is regulated before correlation with TLR9-dependent actions mediated by bacterial DNA or synthetic ODNs as their agonists.…”

Expression and Functional Characterization of the RIG-I-Like Receptors MDA5 and LGP2 in Rainbow Trout (Oncorhynchus mykiss)

“…In teleost fish, orthologs of human TLRs which recognize viruses have been reported in zebrafish (4,16,21), rainbow trout (19,23), Atlantic salmon (28), grass carp (29), and gilthead sea bream (6). Concerning RLRs, recent studies by our group and others have demonstrated that fish also possess RLR molecules, among which RIG-I and MAVS have been shown to activate the interferon response via a mitochondrionassociated signaling pathway (2,14,36).…”

Characterization, molecular cloning, and expression analysis of Ecsit in the spinyhead croaker, Collichthys lucidus

“…In recent years, many TLRs and MYD88 proteins (important adaptor proteins involved in the TLR signaling pathway) have been studied. For instance, MYD88 (Yao et al, 2009), TLR1 , TLR2 (Baoprasertkul et al, 2007a), TLR3 (Baoprasertkul et al, 2006), TLR4 (Jault et al, 2004), TLR5 (Baoprasertkul et al, 2007b), TLR7 and TLR8 , TLR9 (Franch et al, 2006), TLR20 and TLR21 (Baoprasertkul et al, 2007b;Rebl et al, 2007) have been identified and characterized in fishes. However, only a few Ecsits have so far been identified in species other than mammals.…”