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:A large proportion of indigenous African (IA) colorectal cancer (CRC) patients in South Africa are young (<50years), with no unique histopathological or molecular characteristics. Anatomical site as well as microsatellite instability (MSI) status have shown to be associated with different clinicopathological and molecular features. This study aimed to ascertain key histopathological and miRNA expression patterns in microsatellite stable (MSS) and low-frequency MSI (MSI-L) patients, to provide insight into the mechanism of the disease. This study revealed distinct histopathological features for Left Colon Cancer (LCC), and suggests BAT25/26, miRNAs let-7a-5p and miRNA-125a/b-5p as negative prognostic markers in African CRC patients.
Project description:In the present study, we have analyzed the peripheral blood leukocyte (PBL) transcriptome of eight natural M. bovis-infected and eight age- and sex-matched non-infected control Holstein-Friesian animals using RNA-seq. In addition, we compared gene expression profiles generated using RNA-seq with those previously generated using the high-density Affymetrix® GeneChip® Bovine Genome Array platform from the same PBL-extracted RNA
Project description:GeneSeek HD Bovine 77k Genotyping array is used to estimate population structure and ancestry of bovine and evaluate loci responsible for complex traits. Further, copy number variation of bovine can be estimated by GeneSeek HD Bovine 77k Genotyping array. Here, we estimate population structure and ancestry of Qinchuan cattle.
Project description:Animal African trypanosomosis, caused by blood protozoan parasites transmitted mainly by tsetse flies, represents a major constraint for millions of cattle in sub-Saharan Africa. Exposed cattle include West African taurine breeds called trypanotolerant according to their ability to control parasite development and to survive and grow in enzootic areas, and indicine breeds that are trypanosusceptible to the disease. Until now the genetic basis of trypanotolerance remains unclear. Here, we improved knowledge in the biological processes involved in trypanotolerance by identifying bovine genes differentially expressed during an experimental infection by Trypanosoma congolense and their biological functions. To this end, whole blood genome-wide transcriptome profiling by RNA sequencing was performed on five West African cattle breeds, three trypanotolerant taurine breeds (N'Dama, Lagune and Baoulé), one susceptible zebu (Zebu Fulani) and one African taurine x zebu admixed breed (Borgou), at four dates, one before and three during infection. As expected, infection had a major impact on cattle blood transcriptome whatever the breed. The functional analysis of differentially expressed genes over time in each breed confirmed an early activation of the innate immune response, followed by an activation of the humoral response and an inhibition of T cells functions at the chronic stage of infection. More importantly, we highlighted overlooked features, as a strong disturbance in host metabolism and cell production energy that differentiate trypantolerant and trypanosusceptible breeds. N'Dama breed showed the earliest regulation of immune response, associated with a strong activation of cellular energy production, this last feature being also shared with Lagune, and to a lesser extent with Baoulé. Susceptible Zebu Fulani breed was distinguished from other breeds by the strongest modification in lipid metabolism regulation. Lastly, basal differences in gene expression reflected the structuration of cattle genetic diversity, and could have consequences on the tolerant or susceptible phenotype. Overall, it would be of value to deeper investigate interactions between immune response and cell metabolism that likely impact disease outcome.
Project description:Bovine tropical theileriosis is a major haemoprotozoan disease associated with high rates of morbidity and mortality particularly in exotic and crossbred cattle. It is one of the major constraints for of the livestock development programmes in India and southern Asia. Indigenous cattle (Bos indicus) are less affected by this disease than exotic and crossbred cattle. Genetic basis of resistance to tropical theileriosis in indigenous cattle is not well studied. Recent studies gives an idea that differentially genes expressed in exotic and indigenous breeds play an important role in breed specific resistance to tropical theileriosis. The present study was designed to visualize the global gene expression profiling in PBMCs derived from indigenous (Tharparkar) and crossbred cattle with in vitro infection of T. annulata. T. annulata Parbhani strain, originally isolated from Maharashtra (India) and maintained as cryopreserved stabilates of ground-up tick tissue sporozoite (GUTS) of infected H. anatolicum anatolicum was used as infective material. Two separate microarray experiments were carried out using separately each for crossbred and Tharparkar cattle. The crossbred cattle showed 1082 differentially expressed genes (DEGs). Out of total DEGs, 597 genes were downregulated and 485 were upregulated. Their fold change varies from 2283.93 to -4816.02. Tharparkar cattle showed 875 differentially expressed genes. Out of total DEGs in Tharparkar cattle, 451 genes were downregulated and 424 genes were upregulated. Their fold change varies from 94.93 to -19.20. A subset of genes was validated by quantitative RT-PCR and results correlated well with data obtained from the microarrays indicating that the microarray results gave an accurate report of transcript level. Functional annotation study of differentially expressed genes has confirmed their involvement in various pathways including response to oxidative stress, immune system regulation, cell proliferation, cytoskeletal changes, kinases activity and apoptosis. Gene network analysis of these differentially expressed genes provided an effective way to understand the interaction among them. It is therefore, hypothesised that the dissimilar susceptibility to tropical theileriosis exhibited by indigenous and crossbred cattle is due to breed-specific differences in the interaction of infected cells with other immune cells, which ultimately influences the immune response generated against T. annulata infection. Global gene expression profiling in PBMCs derived from indigenous (Tharparkar) and crossbred cattle were studied after in vitro infection of T. annulata Parbhani strain at 2h time period. Two separate microarray experiments were carried out using Bovine (V2) Gene Expression Microarray, 4x44K (Agilent). Two biological replicate samples were profiled per condition (i.e. replicates samples each in crossbred and Tharparkar cattle).