Project description:This study examined tolerance to hypoxia-induced pulmonary hypertension in yearling beef cattle raised at high elevation (7120 ft/2170m).
Project description:The transcriptome signature of peripheral blood mononuclear cells (PBMCs) of Ladakhi cattle adapted to high altitude vis a vis Sahiwal cattle adapted to the arid/semi-arid region at mean sea level was established using bovine expression microarray chips. The transcriptome analysis of PBMCs from these cattle types living at two distinct altitudes, resulted in identification of several hundred differentially expressed genes, biological processes, molecular functions and pathways.
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:Purpose: High-altitude adaptive evolution of transcription, and the convergence and divergence of transcriptional alteration across species in response to high-altitude environments, is an important topic of broad interest to the general biology community. Our study aims to answer this important biological question. Methods: We generated deep transcriptome data of high- and low- altitude populations across four species: chicken, pig, goat and sheep, as well as high-altitude yak and low-altitude cattle, from six tissues (heart, kidney, liver, lung, skeletal muscle and spleen). Results: Here we provide a comprehensive comparative transcriptome landscape of expression and alternative splicing variation between low- and high-altitude populations across multiple species for distinct tissues. Conclusions: Our data serves a valuable resource for further study on adaptive transcription evolution and identification of candidate adaptive genes.
Project description:The biological mechanisms associated with the residual feed intake in ruminants have been harnessed immensely via transcriptome analysis of liver and ruminal epithelium, however, this concept has not been fully explored using whole blood. We applied whole blood transcriptome analysis and gene set enrichment analysis to identify key pathways associated with divergent selection for low or high RFI in beef cattle. A group of 56 crossbred beef steers (average BW = 261.3 ± 18.5 kg) were adapted to a high-forage total mixed ration in a confinement dry lot equipped with GrowSafe intake nodes for period of 49 d to determine their residual feed intake (RFI). After RFI determination, weekly whole blood samples were collected three times from beef steers with the lowest RFI (most efficient; low-RFI; n = 8) and highest RFI (least efficient; high-RFI; n = 8). Prior to RNA extraction, whole blood samples collected were composited for each steer. Sequencing was performed on an Illumina NextSeq2000 equipped with a P3 flow. Gene set enrichment analysis (GSEA) was used to analyze differentially expressed gene sets and pathways between the two groups of steers. Results of GSEA revealed pathways associated with metabolism of proteins, cellular responses to external stimuli, stress, and heat stress were differentially inhibited (false discovery rate (FDR) < 0.05) in high-RFI compared to low-RFI beef cattle, while pathways associated with binding and uptake of ligands by scavenger receptors, scavenging of heme from plasma, and erythrocytes release/take up oxygen were differentially enriched (FDR < 0.05) in high-RFI, relative to low-RFI beef cattle. Taken together, our results revealed that beef steers divergently selected for low or high RFI revealed differential expressions of genes related to protein metabolism and stress responsiveness.
Project description:This study explores how yaks, an ideal animal model for studying plateau adaptability, adapt to high-altitude environments. The lung is a representative organ of the yak’s adaptation to high-altitude environments. The F1 hybrids of yak and cattle, known as dzho, also exhibit adaptability to plateau conditions. This study constructed a single-cell transcriptome atlas of the lungs in yak, dzho and cattle, containing 51 subtypes. We initially found that the differential subtypes among yak, dzho and cattle were mainly concentrated in T&NK cells and fibroblasts. Most of them belonged to new cell subtypes. Subsequently, we speculated that NKG7 and CD4 played a central regulatory role in T&NK cells, contributing to T cell activation and affecting the adaptive immune response of yaks. In fibroblasts, MYL9 and IGF2 are believed to play key regulatory roles, participating in maintaining cellular energy metabolism balance. These results provide an important scientific basis for systematically analysing the molecular regulatory mechanisms of yak adaptation to high-altitude hypoxia.
Project description:Transcriptome signature of local native cattle of Ladakh region from high altitude and Sahiwal cattle from low altitude (sea level).
Project description:We profiled blood transcriptomics of 24 beef steers at three important stages (Entry: on arrival at the feedlot; Pulled: when sickness is identified; and Close-out: recovered, healthy cattle at shipping to slaughter) to reveal the key biological functions and regulatory factors of BRD and identify gene markers of BRD for early diagnosis and potentially use in selection.
Project description:Understanding molecular mechanism associated with high altitude exposure during acclimatization/adaptation/maladaptation. Data reveals specific components of the complex molecular circuitry underlying high altitude pulmonary edema. Individualized outcome prediction were constructed through expression profiling of 39400 genes in sea level sojourners who were acclimatized to high altitude and grouped as controls (n=14), high altitude natives (n=14) and individuals who developed high altitude pulmonary edema within 48-72 hours after air induction to high altitude (n=17).