Project description:Comparative microarray analysis of Rhipicephalus (Boophilus) microplus expression profiles of larvae pre-attachment and feeding adult female stages on Bos indicus and B. taurus cattle Global analysis of gene expression changes in R. microplus during larval, pre-attachment and early adult stages of its life cycle feeding on Bos indicus and Bos taurus cattle were compared using gene expression microarray analysis. Among the 13 601 R. microplus transcripts from BmiGI Version 2 we identified 297 up and 17 down regulated transcripts were differentially expressed between R. microplus feeding on tick resistant cattle [Bos indicus (Brahman)] compared to R. microplus feeding on tick susceptible cattle [Bos taurus (Holstein-Friesian)]. These include genes encoding enzymes involved in primary metabolism, and genes related to stress, defence, cell wall modification, cellular signaling, receptor and cuticle. Microarrays were validated by qRT-PCR analysis of selected transcripts including the validation of three housekeeping genes. The analysis of all tick stages under survey suggested a coordinated regulation of defence proteins, proteases, and protease inhibitors to achieve successful attachment and survival of R. microplus on different host breeds particularly Bos indicus cattle.
Project description:This experiment was undertaken to document changes in gene expression in the skin of tick-resistant Brahman (Bos indicus) and tick-susceptible Holstein-Friesian (Bos taurus) cattle prior to, and following, infestation with the cattle tick Rhipicephalus (Boophilus) microplus Experiment Overall Design: RNA was extracted from skin samples of tick-naïve cattle (animals with no previous R.microplus exposure) and tick-infested cattle after a period of successive, heavy infestations with R. microplus. Skin samples taken from tick-infested animals were taken at sites where tick larvae (approximately 24 h old) were attached to the skin sample. Skin samples were of 8 mm diameter and full skin thickness (approximately 10 mm). RNA samples from 12 animals (3 tick-naive Holstein-Friesian, 3 tick-naive Brahman, 3 tick-infested Holstein-Friesian and 3 tick-infested Brahman) were processed and hybridised to individual slides.
Project description:Comparative microarray analysis of Rhipicephalus (Boophilus) microplus expression profiles of larvae pre-attachment and feeding adult female stages on Bos indicus and B. taurus cattle Global analysis of gene expression changes in R. microplus during larval, pre-attachment and early adult stages of its life cycle feeding on Bos indicus and Bos taurus cattle were compared using gene expression microarray analysis. Among the 13 601 R. microplus transcripts from BmiGI Version 2 we identified 297 up and 17 down regulated transcripts were differentially expressed between R. microplus feeding on tick resistant cattle [Bos indicus (Brahman)] compared to R. microplus feeding on tick susceptible cattle [Bos taurus (Holstein-Friesian)]. These include genes encoding enzymes involved in primary metabolism, and genes related to stress, defence, cell wall modification, cellular signaling, receptor and cuticle. Microarrays were validated by qRT-PCR analysis of selected transcripts including the validation of three housekeeping genes. The analysis of all tick stages under survey suggested a coordinated regulation of defence proteins, proteases, and protease inhibitors to achieve successful attachment and survival of R. microplus on different host breeds particularly Bos indicus cattle. The microarray was conducted by NimbleGen Systems Inc following the method reported by Saldivar [Saldivar L et al., Insect Mol Biol 2008, 17(6):597-606]. 10 samples: 2 larva, 2 pre-attachment larva in B. indicus and 2 in B. taurus, and 2 adult ticks in B. indicus and 2 in B. taurus
Project description:Here we describe a genome-wide analysis of copy number variations (CNVs) in Chinese domestic cattle by using array comparative genomic hybridization (array CGH) and quantitative PCR (qPCR). We conducted array CGH analysis on 30 male cattle individuals, animals from consisting of 12 breeds of Bos taurus/Bos indicus, 1 Bos grunniens and and two ones of Bubalus bubalis breeds for with beef, and/or dairy or dual purpose. We identified over 470 candidate CNV regions (CNVRs) in Bos B. taurus/B. indicus; 118 candidate CNV regions (CNVRs) in B. grunniens, 139 CNVRs in B. bubalis. Furthermore, based on the Y haplotypes of B. taurus/ B. indicus, Wwe also identified 69, 337, and 251 candidate CNV regions (CNVRs) in the sub-groups of Y1, Y2 and Y3 haplotypes.
Project description:Copy number variations (CNVs) have been demonstrated as crucial substrates for evolution, adaptation and breed formation. Chinese indigenous cattle breeds exhibit a broad geographical distribution and diverse environmental adaptability. Here, we analyzed the population structure and adaptation to high altitude of Chinese indigenous cattle based on genome-wide CNVs derived from the high-density BovineHD SNP array. We successfully detected the genome-wide CNVs of 318 individuals from 24 Chinese indigenous cattle breeds and 37 yaks as outgroups. A total of 5,818 autosomal CNV regions (683 bp - 4,477,860 bp in size), covering ~14.34% of the bovine genome (UMD3.1), were identified, showing abundant CNV resources. Neighbor-joining clustering, principal component analysis (PCA), and population admixture analysis based on these CNVs support that most Chinese cattle breeds are hybrids of Bos taurus taurus (hereinafter to be referred as Bos taurus) and Bos taurus indicus (Bos indicus). The distribution patterns of the CNVs could to some extent be related to the geographical backgrounds of the habitat of the breeds, and admixture among cattle breeds from different districts. We analyzed the selective signatures of CNVs positively involved in high-altitude adaptation using pairwise Fst analysis within breeds with a strong Bos taurus background (taurine-type breeds) and within Bos taurus×Bos indicus hybrids, respectively. CNV-overlapping genes with strong selection signatures (at top 0.5% of Fst value), including LETM1 (Fst = 0.490), TXNRD2 (Fst=0.440) and STUB1 (Fst=0.420) within taurine-type breeds, and NOXA1 (Fst = 0.233), RUVBL1 (Fst=0.222) and SLC4A3 (Fst=0.154) within hybrids, were potentially involved in the adaptation to hypoxia. Thus, we provide a new profile of population structure from the CNV aspects of Chinese indigenous cattle and new insights into high-altitude adaptation in cattle.
Project description:Tropical theileriosis in a cattle disease of global economic importance, caused by the tick-borne protozoan parasite Theileria annulata. Conventional control strategies are failing to contain the disease and an attractive alternative is the use of pre-existing genetic resistance or tolerance. However, tropical theileriosis tolerant cattle are less productive than some susceptible breeds. To combine resistance and production traits requires an understanding of the mechanisms involved in resistance. Therefore, we have compared the response of monocytes derived from tolerant (Sahiwals, Bos indicus) and susceptible (Holstein-Friesians, B. taurus) cattle to in vitro infection with T. annulata. Over 150 genes exhibited breed-specific differential expression during the course of infection and nearly one third were differentially expressed in resting cells, implying that there are inherent differences between monocytes from the breeds. Fifty sequences currently only match ESTs or are unique to the library used to generate the microarray. The differential expression of a selection of genes was validated by quantitative RT-PCR, e.g. CD9, prion protein and signal-regulatory protein alpha. A large proportion of the differentially expressed genes encode proteins expressed on the plasma membrane or in the extracellular space and cell adhesion was one of the major Gene Ontology biological processes identified. We therefore hypothesise that the breed-specific tolerance of Sahiwal cattle compared to Holstein-Friesians is due to the interaction of infected cells with other immune cells, which influences the immune response generated against T. annulata infection. The BoMP microarray is available from the ARK-Genomics facility (www.ark-genomics.org).