ISSN : 1225-3480
Toll-like receptors (TLRs) are a major pattern recognition receptor that recognize the structure of invading pathogen and play key roles by triggering immune response. In this study, we identified a sequence of TLR homolog and characterized at molecular level from the abalone (Haliotis discus hannai). Multiple alignments and phylogenetic analysis of abalone TLR protein belongs to the TLR 2/6. Expression level of abalone TLR2/6 in the tissue was comparatively high in the mantle, gill, digestive duct, and hemocytes, but lowest in the muscle. Expression level of abalone TLR2/6 mRNA in the mantle, gill, digestive duct, and hemocytes was 20-fold, 60-fold, 115-fold, 112-fold higher than in the muscle, respectively. Expression level of abalone TLR2/6 mRNA in the mantle was steadily increased until 12 h and decreased post-infection with Vibrio parahemolyticus. While the expression level of abalone TLR2/6 mRNA in the gill and hemocytes was drastically increased at 6 and 9 h post-infection with Vibrio parahemolyticus, respectively. These results suggest that abalone TLR2/6 is conserved through evolution and may play roles similar to its mammalian counterparts.
Bell JK, Mullen GE, Leifer CA, Mazzoni A, Davies DR, Segal DM. (2003) Leucine-rich repeats, pathogen recognition in Toll-like receptors. Trends Immunology, 24(10): 528-533.
Bilodeau A.L., Waldbieser G.C. (2005) Activation of TLR3, TLR5 in channel catfish exposed to virulent Edwardsiella ictaluri. Developmental, Comparative Immunology, 29: 713-721.
Casanova J.L., Abel L., Quintana-Murci L. (2011)Human TLRs, IL-1Rs in host defense: natural insights from evolutionary, epidemiological,, clinical genetics. Annual Reviews of Immunology, 29:447-491.
Cook DN, Pisetsky DS, Schwartz DA. (2004)Toll-like receptors in the pathogenesis of human disease. Nature Immunology, 5(10): 975-979.
Donaghy, L., Lambert, C., Choi, K. S., Soudant, P. (2009) Hemocytes of the carpet shell clam (Ruditapes decussatus), the Manila clam (Ruditapes philippinarum), current knowledge, future prospects. Aquaculture, 297: 10-24.
Elvitigala DA, Premachandra HK, Whang I, Nam BH, Lee J. (2013) Molecular insights of the first gastropod TLR counterpart from disk abalone (Haliotis discus discus), revealing its transcriptional modulation under pathogenic stress. Fish, Shellfish Immunology, 35: 334-342.
Iwanaga S, Lee BL. (2005) Recent advances in the innate immunity of invertebrate animals. Journal of Biochemistry, Molecular Biology, 38(2): 128-150
Jeong, J.E., Lee, Y.S. (2013) Identification, sequence characterization, expression analysis of the arginine kinase gene in response to laminarin challenge from the Oriental land snail, Nesiohelix samarangae. Korean Journal of Malacology, 29:71-179.
Livak, K.J., Schmittgen, T.D. (2001) Analysis of relative gene expression data using real-time quantitative PCR, the 2-△△CT method. Methods, 25: 402-408.
Medzhitov R. (2001) Toll-like receptors, innate immunity. Nature Reviews Immunology, 1(2): 135-45.
Moon J.Y., Nam B.H., Kong H.J., Kim Y.O., Kim W.J., Kim B.S., Kim K.K., Lee S.J. (2011) Maximal transcriptional activation of piscine soluble Toll-like receptor 5 by the NF-κB subunit p65, flagellin. Fish, Shellfish Immunology, 31(6): 881-886.
Oshiumi H., Tsujita T., Shida K., Matsumoto M., Ikeo K., Seya T. (2003) Prediction of the prototype of the human Toll-like receptor gene family from the pufferfish, Fugu rubripes, genome. Immunogenetics, 54: 791-800.
Qiu L, Song L, Xu W, Ni D, Yu Y. (2007) Molecular cloning, expression of a Toll receptor gene homologue from Zhikong Scallop, Chlamys farreri. Fish, Shellfish Immunology, 22: 451-66.
Sabina Kaczanowska, Ann Mary Joseph, Eduardo Davila (2013) TLR agonists: our best frenemy in cancer immunotherapy. Journal of Leukocyte Biology, 93(6):847-863.
Sabroe I., Read R.C., Whyte M.K., Dockrell D.H., Vogel S.N., Dower S.K. (2003) Toll-like receptors in health, disease: complex questions remain. Journal of Immunology, 171(4): 1630-1635.
Shanmugam A., Rajoria S., George A.L., Mittelman A., Suriano R., Tiwari R.K. (2012) Synthetic Toll like receptor-4 (TLR-4) agonist peptides as a novel class of adjuvants. PLoS One, 7(2): e30839.
Toubiana M.., Gerdol M., Rosani U., Pallavicini A., Venier P., Roch P. (2013) Toll-like receptors, MyD88 adaptors in Mytilus: complete cds, gene expression levels. Developmental, Comparative Immunology, 40: 158-166.
Toubiana M., Rosani U., Giambelluca S., Cammarata M., Gerdol M., Pallavicini A., Venier P., Roch P. (2014) Toll signal transduction pathway in bivalves:complete cds of intermediate elements, related gene transcription levels in hemocytes of immune stimulated Mytilus galloprovincialis. Developmental, Comparative Immunology, 45: 300-312
Uematsu S., Akira S. (2008) Toll-Like receptors (TLRs), their ligands. Handbook Experimental Pharmacology, 183: 1-20.
Wootton E.C., Dyrynda E.A., Ratcliffe N.A. (2003)Bivalve immunity: comparisons between the marine mussel (Mytilus edulis), the edible cockle (Cerastoderma edule), the razor-shell (Ensis siliqua). Fish, Shellfish Immunology, 15: 195-210.
Zhang L., Li L., Zhang G. (2011) A Crassostrea gigas Toll-like receptor, comparative analysis of TLR pathway in invertebrates. Fish, Shellfish Immunology, 30: 653-660.
Zhang Y., He X., Yu F., Xiang Z., Li J., Thorpe K.L., Yu Z. (2013) Characteristic, functional analysis of toll-like receptors (TLRs) in the lophotrocozoan, Crassostrea gigas, reveals ancient origin of TLR-mediated innate immunity. PLoS One, 8: e76464.
