Cloning and radiation hybrid mapping of bovine toll-like receptor-4 (TLR-4) signaling molecules.
Toll-like receptor (TLR)-4 is a transmembrane receptor for lipopolysaccharide, a highly pro-inflammatory component of the outer membrane of Gram-negative bacteria. To date, molecules of the TLR-4 signaling pathway have not been well characterized in cattle. The goal of this study was to clone and sequence the full-length coding regions of bovine genes involved in TLR-4 signaling including CASP8, IRAK1, LY96 (MD-2), TICAM2, TIRAP, TOLLIP and TRAF 6 and to position these genes, as well as MyD88 and TICAM1, on the bovine genome using radiation hybrid mapping. Results of this work indicate differences with a previously published bovine sequence for LY96 and a predicted sequence in the GenBank database for TIRAP based on the most recent assembly of the bovine genome. In addition, discrepancies between actual and predicted chromosomal map positions based on the Btau_2.0 genome assembly release were identified, although map positions were consistent with predicted locations based on the current bovine-human comparative map. Alignment of the bovine amino acid sequences with human and murine sequences showed a broad range in conservation, from 52 to 93%. Overall, this work should assist in the assembly and annotation of the bovine genome sequence, the identification of variations in genes critically involved in host innate immunity, and facilitate the study of TLR-4 signaling pathways in cattle.
Connor
Erin E
EE
Bovine Functional Genomics Laboratory, U.S. Department of Agriculture, Agricultural Research Service, Beltsville, MD 20705, USA.
Cates
Elizabeth A
EA
Williams
John L
JL
Bannerman
Douglas D
DD
D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D053181:Caspase 8; D020169:Caspases / Q000737:chemistry / Q000235:genetics; D002417:Cattle / Q000276:immunology*; D003001:Cloning, Molecular; D053592:Interleukin-1 Receptor-Associated Kinases; D047908:Intracellular Signaling Peptides and Proteins / Q000737:chemistry / Q000235:genetics; D051218:Lymphocyte Antigen 96 / Q000737:chemistry / Q000235:genetics; D053594:Myeloid Differentiation Factor 88; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry / Q000235:genetics; D021101:Radiation Hybrid Mapping / Q000662:veterinary; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D015398:Signal Transduction / Q000276:immunology; D048029:TNF Receptor-Associated Factor 6 / Q000737:chemistry / Q000235:genetics; D051197:Toll-Like Receptor 4 / Q000235:genetics* / Q000276:immunology*
D048868:Adaptor Proteins, Signal Transducing; D047908:Intracellular Signaling Peptides and Proteins; D051218:Lymphocyte Antigen 96; C507779:MYD88 protein, human; D053594:Myeloid Differentiation Factor 88; D048029:TNF Receptor-Associated Factor 6; D051197:Toll-Like Receptor 4; C507768:IRAK1 protein, human; D053592:Interleukin-1 Receptor-Associated Kinases; D017346:Protein Serine-Threonine Kinases; C505530:CASP8 protein, human; D053181:Caspase 8; D020169:Caspases