College of Agriculture & Natural Resources

Permanent URI for this communityhttp://hdl.handle.net/1903/1598

The collections in this community comprise faculty research works, as well as graduate theses and dissertations.

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Subject: search.filters.subject.Cattle

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Now showing 1 - 6 of 6
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    Are CD45RO+ and CD45RA- genuine markers for bovine memory T cells?
    (Springer Nature, 2022-10-11) Anmol, Kandel; Akanksha, Hada; Zhengguo, Xiao
    Effective vaccination induces memory T cells, which protect the host against pathogen re-infections. Therefore, detection of memory T cells is essential for evaluating vaccine efficacy, which was originally dependent on cytokine induction assays. Currently, two isoforms of CD45 tyrosine phosphatase, CD45RO expression and CD45RA exclusion (CD45RO+/ CD45RA-) are used extensively for detecting memory T cells in cattle. The CD45RO+/CD45RA- markers were first established in humans around three decades ago, and were adopted in cattle soon after. However, in the last two decades, some published data in humans have challenged the initial paradigm, and required multiple markers for identifying memory T cells. On the contrary, memory T cell detection in cattle still mostly relies on CD45RO+/CD45RA- despite some controversial evidence. In this review, we summarized the current literature to examine if CD45RO+/CD45RA- are valid markers for detecting memory T cells in cattle. It seems CD45RA and CD45RO (CD45RA/RO) as markers for identifying bovine memory T cells are questionable.
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    Genome-wide recombination map construction from single sperm sequencing in cattle
    (Springer Nature, 2022-03-05) Yang, Liu; Gao, Yahui; Li, Mingxun; Park, Ki-Eun; Liu, Shuli; Kang, Xiaolong; Liu, Mei; Oswalt, Adam; Fang, Lingzhao; Telugu, Bhanu P.; Sattler, Charles G.; Li, Cong-jun; Cole, John B.; Seroussi, Eyal; Xu, Lingyang; Yang, Lv; Zhou, Yang; Li, Li; Zhang, Hongping; Rosen, Benjamin D.; Van Tassell, Curtis P.; Ma, Li; Liu, George E.
    Meiotic recombination is one of the important phenomena contributing to gamete genome diversity. However, except for human and a few model organisms, it is not well studied in livestock, including cattle. To investigate their distributions in the cattle sperm genome, we sequenced 143 single sperms from two Holstein bulls. We mapped meiotic recombination events at high resolution based on phased heterozygous single nucleotide polymorphism (SNP). In the absence of evolutionary selection pressure in fertilization and survival, recombination events in sperm are enriched near distal chromosomal ends, revealing that such a pattern is intrinsic to the molecular mechanism of meiosis. Furthermore, we further validated these findings in single sperms with results derived from sequencing its family trio of diploid genomes and our previous studies of recombination in cattle. To our knowledge, this is the first large-scale single sperm whole-genome sequencing effort in livestock, which provided useful information for future studies of recombination, genome instability, and male infertility.
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    Towards the detection of copy number variation from single sperm sequencing in cattle
    (Springer Nature, 2022-03-17) Yang, Liu; Gao, Yahui; Oswalt, Adam; Fang, Lingzhao; Boschiero, Clarissa; Neupane, Mahesh; Sattler, Charles G.; Li, Cong-jun; Seroussi, Eyal; Xu, Lingyang; Yang, Lv; Li, Li; Zhang, Hongping; Rosen, Benjamin D.; Van Tassell, Curtis P.; Zhou, Yang; Ma, Li; Liu, George E.
    Copy number variation (CNV) has been routinely studied using bulk-cell sequencing. However, CNV is not well studied on the single-cell level except for humans and a few model organisms. We sequenced 143 single sperms of two Holstein bulls, from which we predicted CNV events using 14 single sperms with deep sequencing. We then compared the CNV results derived from single sperms with the bulk-cell sequencing of one bull’s family trio of diploid genomes. As a known CNV hotspot, segmental duplications were also predicted using the bovine ARS-UCD1.2 genome. Although the trio CNVs validated only some single sperm CNVs, they still showed a distal chromosomal distribution pattern and significant associations with segmental duplications and satellite repeats. Our preliminary results pointed out future research directions and highlighted the importance of uniform whole genome amplification, deep sequence coverage, and dedicated software pipelines for CNV detection using single cell sequencing data.
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    Dissection of additive, dominance, and imprinting effects for production and reproduction traits in Holstein cattle
    (Springer Nature, 2017-05-30) Jiang, Jicai; Shen, Botong; O’Connell, Jeffrey R.; VanRaden, Paul M.; Cole, John B.; Ma, Li
    Although genome-wide association and genomic selection studies have primarily focused on additive effects, dominance and imprinting effects play an important role in mammalian biology and development. The degree to which these non-additive genetic effects contribute to phenotypic variation and whether QTL acting in a non-additive manner can be detected in genetic association studies remain controversial. To empirically answer these questions, we analyzed a large cattle dataset that consisted of 42,701 genotyped Holstein cows with genotyped parents and phenotypic records for eight production and reproduction traits. SNP genotypes were phased in pedigree to determine the parent-of-origin of alleles, and a three-component GREML was applied to obtain variance decomposition for additive, dominance, and imprinting effects. The results showed a significant non-zero contribution from dominance to production traits but not to reproduction traits. Imprinting effects significantly contributed to both production and reproduction traits. Interestingly, imprinting effects contributed more to reproduction traits than to production traits. Using GWAS and imputation-based fine-mapping analyses, we identified and validated a dominance association signal with milk yield near RUNX2, a candidate gene that has been associated with milk production in mice. When adding non-additive effects into the prediction models, however, we observed little or no increase in prediction accuracy for the eight traits analyzed. Collectively, our results suggested that non-additive effects contributed a non-negligible amount (more for reproduction traits) to the total genetic variance of complex traits in cattle, and detection of QTLs with non-additive effect is possible in GWAS using a large dataset.
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    Analyses of inter-individual variations of sperm DNA methylation and their potential implications in cattle
    (Springer Nature, 2019-11-21) Liu, Shuli; Fang, Lingzhao; Zhou, Yang; Santos, Daniel J.A.; Xiang, Ruidong; Daetwyler, Hans D.; Chamberlain, Amanda J.; Cole, John B.; Li, Cong-jun; Yu, Ying; Ma, Li; Zhang, Shengli; Liu, George E.
    DNA methylation has been shown to be involved in many biological processes, including X chromosome inactivation in females, paternal genomic imprinting, and others.
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    Comparative whole genome DNA methylation profiling across cattle tissues reveals global and tissue-specific methylation patterns
    (Springer Nature, 2020-07-06) Zhou, Yang; Liu, Shuli; Hu, Yan; Fang, Lingzhao; Gao, Yahui; Xia, Han; Schroeder, Steven G.; Rosen, Benjamin D.; Connor, Erin E.; Li, Cong-jun; Baldwin, Ransom L.; Cole, John B.; Van Tassell, Curtis P.; Yang, Liguo; Ma, Li; Liu, George E.
    Efforts to improve animal health, and understand genetic bases for production, may benefit from a comprehensive analysis of animal genomes and epigenomes. Although DNA methylation has been well studied in humans and other model species, its distribution patterns and regulatory impacts in cattle are still largely unknown. Here, we present the largest collection of cattle DNA methylation epigenomic data to date. Using Holstein cattle, we generated 29 whole genome bisulfite sequencing (WGBS) datasets for 16 tissues, 47 corresponding RNA-seq datasets, and 2 whole genome sequencing datasets. We did read mapping and DNA methylation calling based on two different cattle assemblies, demonstrating the high quality of the long-read-based assembly markedly improved DNA methylation results. We observed large differences across cattle tissues in the methylation patterns of global CpG sites, partially methylated domains (PMDs), hypomethylated regions (HMRs), CG islands (CGIs), and common repeats. We detected that each tissue had a distinct set of PMDs, which showed tissue-specific patterns. Similar to human PMD, cattle PMDs were often linked to a general decrease of gene expression and a decrease in active histone marks and related to long-range chromatin organizations, like topologically associated domains (TADs). We tested a classification of the HMRs based on their distributions relative to transcription start sites (TSSs) and detected tissue-specific TSS-HMRs and genes that showed strong tissue effects. When performing cross-species comparisons of paired genes (two opposite strand genes with their TSS located in the same HMR), we found out they were more consistently co-expressed among human, mouse, sheep, goat, yak, pig, and chicken, but showed lower consistent ratios in more divergent species. We further used these WGBS data to detect 50,023 experimentally supported CGIs across bovine tissues and found that they might function as a guard against C-to-T mutations for TSS-HMRs. Although common repeats were often heavily methylated, some young Bov-A2 repeats were hypomethylated in sperm and could affect the promoter structures by exposing potential transcription factor binding sites. This study provides a comprehensive resource for bovine epigenomic research and enables new discoveries about DNA methylation and its role in complex traits.