Article

The Genome Sequence of Taurine Cattle: A Window to Ruminant Biology and Evolution

Science 01/2009; 324.
Source: OAI

ABSTRACT To understand the biology and evolution of ruminants, the cattle genome was sequenced to about sevenfold coverage. The cattle genome contains a minimum of 22,000 genes, with a core set of 14,345 orthologs shared among seven mammalian species of which 1217 are absent or undetected in noneutherian (marsupial or monotreme) genomes. Cattle-specific evolutionary breakpoint regions in chromosomes have a higher density of segmental duplications, enrichment of repetitive elements, and species-specific variations in genes associated with lactation and immune responsiveness. Genes involved in metabolism are generally highly conserved, although five metabolic genes are deleted or extensively diverged from their human orthologs. The cattle genome sequence thus provides a resource for understanding mammalian evolution and accelerating livestock genetic improvement for milk and meat production. Yes Yes

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Available from: Alexandre Reymond, Aug 29, 2015
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    • "To refine the Hereford genome MHC class Ia region, we exploited L1 Domino BAC clones that were previously sequenced as part of the cattle genome project (Elsik et al. 2009). Four fully sequenced and largely assembled clones which overlap the MHC class Ia locus were identified: CH240-252J17, CH240-271N5, CH240-103G5, and CH240-463M1 (GenBank: FQ482148, FO681480, FQ482089, and AC182900, respectively). "
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    ABSTRACT: In cattle, there are six classical MHC class I genes that are variably present between different haplotypes. Almost all known haplotypes contain between one and three genes, with an allele of Gene 2 present on the vast majority. However, very little is known about the sequence and therefore structure and evolutionary history of this genomic region. To address this, we have refined the MHC class I region in the Hereford cattle genome assembly and sequenced a complete A14 haplotype from a homozygous Holstein. Comparison of the two haplotypes revealed extensive variation within the MHC class Ia region, but not within the flanking regions, with each gene contained within a conserved 63- to 68-kb sequence block. This variable region appears to have undergone block gene duplication and likely deletion at regular breakpoints, suggestive of a site-specific mechanism. Phylogenetic analysis using complete gene sequences provided evidence of allelic diversification via gene conversion, with breakpoints between each of the extracellular domains that were associated with high guanine-cytosine (GC) content. Advancing our knowledge of cattle MHC class I evolution will help inform investigations of cattle genetic diversity and disease resistance.
    Immunogenetics 07/2015; DOI:10.1007/s00251-015-0859-9 · 2.49 Impact Factor
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    • "Thus, the specific functional background underlying the SCS-BTA18-QTL could not be unambiguously inferred, because aside from mechanisms of immune defense, udder conformation might also contribute to the genetic variability of mastitis susceptibility. Additionally, the chromosomal region enclosing the QTL confidence interval is characterized by a high gene density [26]. Thus, the aim of the present study was to obtain insights into the physiological mechanisms underlying phenotypic variation in mastitis susceptibility, which might help identify molecular pathways and genes affecting mastitis susceptibility due to the SCS-BTA18-QTL using a combined approach of holistic gene expression profiling of primary bovine mammary gland epithelial cells (pbMEC) sampled from heifers that inherited alternative QTL alleles. "
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    Genetics Selection Evolution 06/2011; 43(1):24. DOI:10.1186/1297-9686-43-24 · 3.75 Impact Factor
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    • ") genome sequencing were comprehensively reviewed and published. For the recent progress and development in domestic animals genome sequencing and assembling, a series of publications and studies were published(Table 3), for bovine (Liu 2009; Elsik et al. 2009; Zimin et al. 2009), porcine (Wiedmann et al. 2008; Amaral et al. 2009; Ramos et al. 2009; Isom et al. 2010; Leifer et al. 2010), sheep (Archibald et al. 2010), horse (Bright et al. 2009; Coleman et al. 2010), chicken (Dalloul et al. 2010, Marklund and Carlborg 2010). "
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