RESUMEN
Cathelicidins (CATHLs) are small, cationic antimicrobial peptides that establish an early innate immune defense against infections in mammals. Beyond their wide spectrum of antimicrobial activity, these peptides play important roles in wound repair, chemotactic activity, and apoptosis. Thus, polymorphisms present in bovine CATHLs 2, 5, 6, and 7 could potentially underlie inherited differences in innate immunity and disease resistance. The purpose of the present study was to characterize single nucleotide polymorphisms (SNPs) and insertion-deletion (indel) polymorphisms within the bovine CATHL gene family. Comparative sequence analysis for 10 domestic cattle breeds representing both Bos taurus and Bos indicus revealed 60 SNPs, 7 of which were nonsynonymous and 5 indel mutations. Characterization of these novel polymorphisms is central to developing a firm understanding regarding what effects, if any, nonsynonymous CATHL variation has with respect to bovine innate immunity.
Asunto(s)
Péptidos Catiónicos Antimicrobianos/genética , Bovinos/genética , Polimorfismo Genético , Análisis de Secuencia de ADN , Alelos , Animales , Estudios de Casos y Controles , Bovinos/inmunología , Frecuencia de los Genes , Mutación INDEL/fisiología , Inmunidad Innata/genética , Familia de Multigenes/genética , Mutación Puntual , Proteínas/genética , CatelicidinasRESUMEN
Approximately 3,000 cattle bacterial artificial chromosome (BAC)-end sequences were added to the Illinois-Texas 5,000-rad RH (RH, radiation hybrid) map. The BAC-end sequences selected for mapping are approximately 1 Mbp apart on the human chromosomes as determined by blastn analysis. The map has 3,484 ordered markers, of which 3,204 are anchored in the human genome. Two hundred-and-one homologous synteny blocks (HSBs) were identified, of which 27 are previously undiscovered, 79 are extended, 26 were formed by previously unrecognized breakpoints in 18 previously defined HSBs, and 23 are the result of fusions. The comparative coverage relative to the human genome is approximately 91%, or 97% of the theoretical maximum. The positions of 64% of all cattle centromeres and telomeres were reassigned relative to their positions on the previous map, thus facilitating a more detailed comparative analysis of centromere and telomere evolution. As an example of the utility of the high-resolution map, 22 cattle BAC fingerprint contigs were directly anchored to cattle chromosome 19 [Bos taurus, (BTA) 19]. The order of markers on the cattle RH and fingerprint maps of BTA19 and the sequence-based map of human chromosome 17 [Homo sapiens, (HSA) 17] were found to be highly consistent, with only two minor ordering discrepancies between the RH map and fingerprint contigs. The high-resolution Illinois-Texas 5,000-rad RH and comparative maps will facilitate identification of candidate genes for economically important traits, the phylogenomic analysis of mammalian chromosomes, proofing of the BAC fingerprint map and, ultimately, aid the assembly of cattle whole-genome sequence.