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Chen C, Parejo M, Momeni J, Langa J, Nielsen RO, Shi W, Vingborg R, Kryger P, Bouga M, Estonba A, Meixner M. Population Structure and Diversity in European Honey Bees ( Apismellifera L.)-An Empirical Comparison of Pool and Individual Whole-Genome Sequencing. Genes (Basel) 2022; 13:182. [PMID: 35205227 PMCID: PMC8872436 DOI: 10.3390/genes13020182] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 12/27/2021] [Accepted: 12/30/2021] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Whole-genome sequencing has become routine for population genetic studies. Sequencing of individuals provides maximal data but is rather expensive and fewer samples can be studied. In contrast, sequencing a pool of samples (pool-seq) can provide sufficient data, while presenting less of an economic challenge. Few studies have compared the two approaches to infer population genetic structure and diversity in real datasets. Here, we apply individual sequencing (ind-seq) and pool-seq to the study of Western honey bees (Apis mellifera). METHODS We collected honey bee workers that belonged to 14 populations, including 13 subspecies, totaling 1347 colonies, who were individually (139 individuals) and pool-sequenced (14 pools). We compared allele frequencies, genetic diversity estimates, and population structure as inferred by the two approaches. RESULTS Pool-seq and ind-seq revealed near identical population structure and genetic diversities, albeit at different costs. While pool-seq provides genome-wide polymorphism data at considerably lower costs, ind-seq can provide additional information, including the identification of population substructures, hybridization, or individual outliers. CONCLUSIONS If costs are not the limiting factor, we recommend using ind-seq, as population genetic structure can be inferred similarly well, with the advantage gained from individual genetic information. Not least, it also significantly reduces the effort required for the collection of numerous samples and their further processing in the laboratory.
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Affiliation(s)
- Chao Chen
- Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China;
- Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture and Rural Affairs, Beijing 100093, China
| | - Melanie Parejo
- Department of Genetics, Physical Anthropology and Animal Physiology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain; (J.L.); (A.E.)
- Swiss Bee Research Center, Agroscope, 3003 Bern, Switzerland
| | - Jamal Momeni
- Eurofins Genomics, 8200 Aarhus, Denmark; (J.M.); (R.O.N.); (R.V.)
| | - Jorge Langa
- Department of Genetics, Physical Anthropology and Animal Physiology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain; (J.L.); (A.E.)
| | | | - Wei Shi
- Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China;
- Key Laboratory of Pollinating Insect Biology, Ministry of Agriculture and Rural Affairs, Beijing 100093, China
| | | | - Rikke Vingborg
- Eurofins Genomics, 8200 Aarhus, Denmark; (J.M.); (R.O.N.); (R.V.)
| | - Per Kryger
- Department of Agroecology, Aarhus University, 4200 Slagelse, Denmark;
| | - Maria Bouga
- Lab of Agricultural Zoology and Entomology, Agricultural University of Athens, 11855 Athens, Greece;
| | - Andone Estonba
- Department of Genetics, Physical Anthropology and Animal Physiology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain; (J.L.); (A.E.)
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Liu H, Wang L, Guo Z, Xu Q, Fan W, Xu Y, Hu J, Zhang Y, Tang J, Xie M, Zhou Z, Hou S. Genome-wide association and selective sweep analyses reveal genetic loci for FCR of egg production traits in ducks. Genet Sel Evol 2021; 53:98. [PMID: 34930109 PMCID: PMC8690979 DOI: 10.1186/s12711-021-00684-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 11/10/2021] [Indexed: 12/30/2022] Open
Abstract
Background As a major economic trait in poultry, egg production efficiency attracts widespread interest in breeding and production. However, limited information is available about the underlying genetic architecture of egg production traits in ducks. In this paper, we analyzed six egg production-related traits in 352 F2 ducks derived from reciprocal crosses between mallard and Pekin ducks. Results Feed conversation ratio (FCR) was positively correlated with feed intake but negatively correlated with egg-related traits, including egg weight and egg production, both phenotypically and genetically. Estimates of pedigree-based heritability were higher than 0.2 for all traits investigated, except hip-width. Based on whole-genome sequencing data, we conducted genome-wide association studies to identify genomic regions associated with these traits. In total, 11 genomic regions were associated with FCR. No genomic regions were identified as significantly associated with hip-width, total feed intake, average daily feed intake, and total egg production. Analysis of selective sweeps between mallard and Pekin ducks confirmed three of these genomic regions on chromosomes 13, 3 and 6. Within these three regions, variants in candidate genes that were in linkage disequilibrium with the GWAS leader single nucleotide polymorphisms (SNPs) (Chr13:2,196,728, P = 7.05 × 10–14; Chr3:76,991,524, P = 1.06 × 10–12; Chr6:20,356,803, P = 1.14 × 10–10) were detected. Thus, we identified 31 potential candidate genes associated with FCR, among which the strongest candidates are those that are highly expressed in tissues involved in reproduction and nervous system functions of ducks: CNTN4, CRBR, GPR63, KLHL32, FHL5, TRNT1, MANEA, NDUFAF4, and SCD. Conclusions For the first time, we report the identification of genomic regions that are associated with FCR in ducks and our results illustrate the genomic changes that occurred during their domestication and are involved in egg production efficiency. Supplementary Information The online version contains supplementary material available at 10.1186/s12711-021-00684-5.
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Affiliation(s)
- Hehe Liu
- State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.,Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 613000, China
| | - Lei Wang
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 613000, China
| | - Zhanbao Guo
- State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Qian Xu
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 613000, China
| | - Wenlei Fan
- State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Yaxi Xu
- State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Jian Hu
- State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Yunsheng Zhang
- State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Jing Tang
- State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Ming Xie
- State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Zhengkui Zhou
- State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China
| | - Shuisheng Hou
- State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
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Liu W, Sun Y, Qiu X, Meng C, Song C, Tan L, Liao Y, Liu X, Ding C. Genome-Wide Analysis of Alternative Splicing during Host-Virus Interactions in Chicken. Viruses 2021; 13:v13122409. [PMID: 34960678 PMCID: PMC8703359 DOI: 10.3390/v13122409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/19/2021] [Accepted: 11/19/2021] [Indexed: 11/16/2022] Open
Abstract
The chicken is a model animal for the study of evolution, immunity and development. In addition to their use as a model organism, chickens also represent an important agricultural product. Pathogen invasion has already been shown to modulate the expression of hundreds of genes, but the role of alternative splicing in avian virus infection remains unclear. We used RNA-seq data to analyze virus-induced changes in the alternative splicing of Gallus gallus, and found that a large number of alternative splicing events were induced by virus infection both in vivo and in vitro. Virus-responsive alternative splicing events preferentially occurred in genes involved in metabolism and transport. Many of the alternatively spliced transcripts were also expressed from genes with a function relating to splicing or immune response, suggesting a potential impact of virus infection on pre-mRNA splicing and immune gene regulation. Moreover, exon skipping was the most frequent AS event in chickens during virus infection. This is the first report describing a genome-wide analysis of alternative splicing in chicken and contributes to the genomic resources available for studying host-virus interaction in this species. Our analysis fills an important knowledge gap in understanding the extent of genome-wide alternative splicing dynamics occurring during avian virus infection and provides the impetus for the further exploration of AS in chicken defense signaling and homeostasis.
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Affiliation(s)
- Weiwei Liu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Yingjie Sun
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Xusheng Qiu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Chunchun Meng
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Cuiping Song
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Lei Tan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Ying Liao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Xiufan Liu
- School of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China;
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China
| | - Chan Ding
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China
- Correspondence: ; Tel.: +86-21-3429-3441
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Guirao‐Rico S, González J. Benchmarking the performance of Pool-seq SNP callers using simulated and real sequencing data. Mol Ecol Resour 2021; 21:1216-1229. [PMID: 33534960 PMCID: PMC8251607 DOI: 10.1111/1755-0998.13343] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 12/21/2020] [Accepted: 01/27/2021] [Indexed: 12/13/2022]
Abstract
Population genomics is a fast-developing discipline with promising applications in a growing number of life sciences fields. Advances in sequencing technologies and bioinformatics tools allow population genomics to exploit genome-wide information to identify the molecular variants underlying traits of interest and the evolutionary forces that modulate these variants through space and time. However, the cost of genomic analyses of multiple populations is still too high to address them through individual genome sequencing. Pooling individuals for sequencing can be a more effective strategy in Single Nucleotide Polymorphism (SNP) detection and allele frequency estimation because of a higher total coverage. However, compared to individual sequencing, SNP calling from pools has the additional difficulty of distinguishing rare variants from sequencing errors, which is often avoided by establishing a minimum threshold allele frequency for the analysis. Finding an optimal balance between minimizing information loss and reducing sequencing costs is essential to ensure the success of population genomics studies. Here, we have benchmarked the performance of SNP callers for Pool-seq data, based on different approaches, under different conditions, and using computer simulations and real data. We found that SNP callers performance varied for allele frequencies up to 0.35. We also found that SNP callers based on Bayesian (SNAPE-pooled) or maximum likelihood (MAPGD) approaches outperform the two heuristic callers tested (VarScan and PoolSNP), in terms of the balance between sensitivity and FDR both in simulated and sequencing data. Our results will help inform the selection of the most appropriate SNP caller not only for large-scale population studies but also in cases where the Pool-seq strategy is the only option, such as in metagenomic or polyploid studies.
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Affiliation(s)
- Sara Guirao‐Rico
- Institute of Evolutionary BiologyCSIC‐Universitat Pompeu FabraBarcelonaSpain
| | - Josefa González
- Institute of Evolutionary BiologyCSIC‐Universitat Pompeu FabraBarcelonaSpain
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Genomic variations and signatures of selection in Wuhua yellow chicken. PLoS One 2020; 15:e0241137. [PMID: 33095808 PMCID: PMC7584229 DOI: 10.1371/journal.pone.0241137] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/08/2020] [Indexed: 02/08/2023] Open
Abstract
Wuhua yellow chicken (WHYC) is an important traditional yellow-feathered chicken from China, which is characterized by its white tail feathers, white flight feathers, and strong disease resistance. However, the genomic basis of these unique traits associated with WHYC is poorly understood. In this study, whole-genome resequencing was performed with an average coverage of 20.77-fold to investigate heritable variation and identify selection signals in WHYC. Reads were mapped onto the chicken reference genome (Galgal5) with a coverage of 85.95%. After quality control, 11,953,471 single nucleotide polymorphisms and 1,069,574 insertion/deletions were obtained. In addition, 41,408 structural variants and 33,278 copy number variants were found. Comparative genomic analysis of WHYC and other yellow-feathered chicken breeds showed that selected regions were enriched in genes involved in transport and catabolism, immune system, infectious diseases, signal transduction, and signaling molecules and interactions. Several genes associated with disease resistance were also identified, including IFNA, IFNB, CD86, IL18, IL11RA, VEGFC, and ATG10. Furthermore, our results suggest that PMEL and TYRP1 may contribute to the white feather coloring in WHYC. These findings can improve our understanding of the genetic characteristics of WHYC and may contribute to future breed improvement.
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Chanthavixay G, Kern C, Wang Y, Saelao P, Lamont SJ, Gallardo RA, Rincon G, Zhou H. Integrated Transcriptome and Histone Modification Analysis Reveals NDV Infection Under Heat Stress Affects Bursa Development and Proliferation in Susceptible Chicken Line. Front Genet 2020; 11:567812. [PMID: 33101389 PMCID: PMC7545831 DOI: 10.3389/fgene.2020.567812] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 09/07/2020] [Indexed: 12/21/2022] Open
Abstract
Two environmental factors, Newcastle disease and heat stress, are concurrently negatively impacting poultry worldwide and warrant greater attention into developing genetic resistance within chickens. Using two genetically distinct and highly inbred layer lines, Fayoumi and Leghorn, we explored how different genetic backgrounds affect the bursal response to a treatment of simultaneous Newcastle disease virus (NDV) infection at 6 days postinfection (dpi) while under chronic heat stress. The bursa is a primary lymphoid organ within birds and is crucial for the development of B cells. We performed RNA-seq and ChIP-seq targeting histone modifications on bursa tissue. Differential gene expression revealed that Leghorn, compared to Fayoumi, had significant down-regulation in genes involved in cell proliferation, cell cycle, and cell division. Interestingly, we also found greater differences in histone modification levels in response to treatment in Leghorns than Fayoumis, and biological processes enriched in associated target genes of H3K27ac and H3K4me1 were similarly associated with cell cycle and receptor signaling of lymphocytes. Lastly, we found candidate variants between the two genetic lines within exons of differentially expressed genes and regulatory elements with differential histone modification enrichment between the lines, which provides a strong foundation for understanding the effects of genetic variation on NDV resistance under heat stress. This study provides further understanding of the cellular mechanisms affected by NDV infection under heat stress in chicken bursa and identified potential genes and regulatory regions that may be targets for developing genetic resistance within chickens.
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Affiliation(s)
- Ganrea Chanthavixay
- Department of Animal Science, University of California, Davis, Davis, CA, United States
| | - Colin Kern
- Department of Animal Science, University of California, Davis, Davis, CA, United States
| | - Ying Wang
- Department of Animal Science, University of California, Davis, Davis, CA, United States
| | - Perot Saelao
- Department of Animal Science, University of California, Davis, Davis, CA, United States
| | - Susan J Lamont
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Rodrigo A Gallardo
- School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | | | - Huaijun Zhou
- Department of Animal Science, University of California, Davis, Davis, CA, United States
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Wang Y, Saelao P, Kern C, Jin S, Gallardo RA, Kelly T, Dekkers JM, Lamont SJ, Zhou H. Liver Transcriptome Responses to Heat Stress and Newcastle Disease Virus Infection in Genetically Distinct Chicken Inbred Lines. Genes (Basel) 2020; 11:E1067. [PMID: 32932855 PMCID: PMC7563548 DOI: 10.3390/genes11091067] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 01/21/2023] Open
Abstract
Heat stress results in reduced productivity, anorexia, and mortality in chickens. The objective of the study was to identify genes and signal pathways associated with heat stress and Newcastle disease virus (NDV) infection in the liver of chickens through RNA-seq analysis, using two highly inbred chicken lines (Leghorn and Fayoumi). All birds were held in the same environment until 14 days of age. On day 14, half the birds were exposed to 38 °C with 50% relative humidity for 4 h, then 35 °C until the end of the experiment. The remaining birds were kept at 25 °C throughout the experiment. The heat-treated birds were inoculated at 21 days of age with 107 EID50 (One EID50 unit is the amount of virus that will infect 50 percent of inoculated embryos) NDV La Sota strain to investigate the effects of both heat stress and NDV infection. Physiological parameters were recorded as blood phenotypes at three stages: acute heat (AH), chronic heat (CH1), and chronic heat combined with NDV infection (CH&NDV), at 4 h, 7 days, and 10 days post-initiation of heat treatment, respectively. Our previous work revealed that the heat-resilient Fayoumi line maintained a more stable acid-base balance in their blood compared to the Leghorn line. Liver samples were harvested on both AH and CH&NDV to characterize the transcriptome profiles of these two inbred lines. Both genetic lines and treatments had large impact on the liver transcriptome. Fayoumi birds had more differentially expressed genes (DEGs) than Leghorn birds for both treatments. Metabolic and immune-related genes were on the DEG list, with Fayoumi having more immune-related DEGs than Leghorns, which was confirmed by gene functional enrichment analysis. Weighted correlation network analysis (WGCNA) indicated that the driver genes such as Solute Carrier Family genes could be very important for stabilizing the acid-base balance in Fayoumi birds during heat stress. Therefore, candidate genes such solute carrier family genes could be potential genetic targets that are regulated by Fayoumis to maintain physical hemostasis under heat stress. Differential gene expression showed that Leghorns mainly performed metabolic regulation in response to heat stress and NDV infection, while Fayoumis regulated both immune and metabolic functions. This study provides novel insights and enhances our understandings of liver response to heat stress of heat resilient and susceptible inbred chicken lines.
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Affiliation(s)
- Ying Wang
- Department of Animal Science, University of California, Davis, CA 95616, USA; (Y.W.); (P.S.); (C.K.); (S.J.)
- Feed the Future Innovation Lab for Genomics to Improve Poultry, University of California, Davis, CA 95616, USA; (R.A.G.); (T.K.); (J.M.D.); (S.J.L.)
| | - Perot Saelao
- Department of Animal Science, University of California, Davis, CA 95616, USA; (Y.W.); (P.S.); (C.K.); (S.J.)
- Feed the Future Innovation Lab for Genomics to Improve Poultry, University of California, Davis, CA 95616, USA; (R.A.G.); (T.K.); (J.M.D.); (S.J.L.)
| | - Colin Kern
- Department of Animal Science, University of California, Davis, CA 95616, USA; (Y.W.); (P.S.); (C.K.); (S.J.)
| | - Sihua Jin
- Department of Animal Science, University of California, Davis, CA 95616, USA; (Y.W.); (P.S.); (C.K.); (S.J.)
| | - Rodrigo A. Gallardo
- Feed the Future Innovation Lab for Genomics to Improve Poultry, University of California, Davis, CA 95616, USA; (R.A.G.); (T.K.); (J.M.D.); (S.J.L.)
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Terra Kelly
- Feed the Future Innovation Lab for Genomics to Improve Poultry, University of California, Davis, CA 95616, USA; (R.A.G.); (T.K.); (J.M.D.); (S.J.L.)
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Jack M. Dekkers
- Feed the Future Innovation Lab for Genomics to Improve Poultry, University of California, Davis, CA 95616, USA; (R.A.G.); (T.K.); (J.M.D.); (S.J.L.)
- Department of Animal Science, Iowa State University, Ames, IA 50011, USA
| | - Susan J. Lamont
- Feed the Future Innovation Lab for Genomics to Improve Poultry, University of California, Davis, CA 95616, USA; (R.A.G.); (T.K.); (J.M.D.); (S.J.L.)
- Department of Animal Science, Iowa State University, Ames, IA 50011, USA
| | - Huaijun Zhou
- Department of Animal Science, University of California, Davis, CA 95616, USA; (Y.W.); (P.S.); (C.K.); (S.J.)
- Feed the Future Innovation Lab for Genomics to Improve Poultry, University of California, Davis, CA 95616, USA; (R.A.G.); (T.K.); (J.M.D.); (S.J.L.)
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Del Vesco AP, Kaiser MG, Monson MS, Zhou H, Lamont SJ. Genetic responses of inbred chicken lines illustrate importance of eIF2 family and immune-related genes in resistance to Newcastle disease virus. Sci Rep 2020; 10:6155. [PMID: 32273535 PMCID: PMC7145804 DOI: 10.1038/s41598-020-63074-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 03/17/2020] [Indexed: 12/12/2022] Open
Abstract
Newcastle disease virus (NDV) replication depends on the translation machinery of the host cell; therefore, the eukaryotic translation initiation factor 2 (eIF2) gene family is a likely candidate for control of viral replication. We hypothesized that differential expression of host genes related to translation and innate immune response could contribute to differential resistance to NDV in inbred Fayoumi and Leghorn lines. The expression of twenty-one genes related to the interferon signaling pathway and the eIF2 family was evaluated at two- and six-days post infection (dpi) in the spleen from both lines, either challenged by NDV or nonchallenged. Higher expression of OASL in NDV challenged versus nonchallenged spleen was observed in Leghorns at 2 dpi. Lower expression of EIF2B5 was found in NDV challenged than nonchallenged Fayoumis and Leghorns at 2 dpi. At 2 dpi, NDV challenged Fayoumis had lower expression of EIF2B5 and EIF2S3 than NDV challenged Leghorns. At 6 dpi, NDV challenged Fayoumis had lower expression of EIF2S3 and EIF2B4 than NDV challenged Leghorns. The genetic line differences in expression of eIF2-related genes may contribute to their differential resistance to NDV and also to understanding the interaction between protein synthesis shut-off and virus control in chickens.
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Affiliation(s)
- Ana Paula Del Vesco
- Department of Animal Science, Iowa State University, Ames, IA, USA
- Department of Animal Science, Universidade Federal de Sergipe, São Cristóvão, SE, Brazil
| | - Michael G Kaiser
- Department of Animal Science, Iowa State University, Ames, IA, USA
| | - Melissa S Monson
- Department of Animal Science, Iowa State University, Ames, IA, USA
| | - Huaijun Zhou
- Department of Animal Science, University of California, Davis, CA, USA
| | - Susan J Lamont
- Department of Animal Science, Iowa State University, Ames, IA, USA.
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Deist MS, Gallardo RA, Dekkers JCM, Zhou H, Lamont SJ. Novel Combined Tissue Transcriptome Analysis After Lentogenic Newcastle Disease Virus Challenge in Inbred Chicken Lines of Differential Resistance. Front Genet 2020; 11:11. [PMID: 32117434 PMCID: PMC7013128 DOI: 10.3389/fgene.2020.00011] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 01/06/2020] [Indexed: 12/15/2022] Open
Abstract
Disease has large negative impacts on poultry production. A more comprehensive understanding of host-pathogen interaction can lead to new and improved strategies to maintain health. In particular, host genetic factors can lead to a more effective response to pathogens, hereafter termed resistance. Fayoumi and Leghorn chicken lines have demonstrated relative resistance and susceptibility, respectively, to the Newcastle disease virus (NDV) vaccine strain and many other pathogens. This biological model was used to better understand the host response to a vaccine strain of NDV across three tissues and time points, using RNA-seq. Analyzing the Harderian gland, trachea, and lung tissues together using weighted gene co-expression network analysis (WGCNA) identified important genes that were co-expressed and associated with parameters including: genetic line, days post-infection (dpi), challenge status, sex, and tissue. Pathways and driver genes, such as EIF2AK2, MPEG1, and TNFSF13B, associated with challenge status, dpi, and genetic line were of particular interest as candidates for disease resistance. Overall, by jointly analyzing the three tissues, this study identified genes and gene networks that led to a more comprehensive understanding of the whole animal response to lentogenic NDV than that obtained by analyzing the tissues individually.
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Affiliation(s)
- Melissa S Deist
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Rodrigo A Gallardo
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Jack C M Dekkers
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Huaijun Zhou
- Department of Animal Science, University of California, Davis, Davis, CA, United States
| | - Susan J Lamont
- Department of Animal Science, Iowa State University, Ames, IA, United States
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10
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Adetunji MO, Lamont SJ, Abasht B, Schmidt CJ. Variant analysis pipeline for accurate detection of genomic variants from transcriptome sequencing data. PLoS One 2019; 14:e0216838. [PMID: 31545812 PMCID: PMC6756534 DOI: 10.1371/journal.pone.0216838] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 09/10/2019] [Indexed: 12/27/2022] Open
Abstract
The wealth of information deliverable from transcriptome sequencing (RNA-seq) is significant, however current applications for variant detection still remain a challenge due to the complexity of the transcriptome. Given the ability of RNA-seq to reveal active regions of the genome, detection of RNA-seq SNPs can prove valuable in understanding the phenotypic diversity between populations. Thus, we present a novel computational workflow named VAP (Variant Analysis Pipeline) that takes advantage of multiple RNA-seq splice aware aligners to call SNPs in non-human models using RNA-seq data only. We applied VAP to RNA-seq from a highly inbred chicken line and achieved high accuracy when compared with the matching whole genome sequencing (WGS) data. Over 65% of WGS coding variants were identified from RNA-seq. Further, our results discovered SNPs resulting from post transcriptional modifications, such as RNA editing, which may reveal potentially functional variation that would have otherwise been missed in genomic data. Even with the limitation in detecting variants in expressed regions only, our method proves to be a reliable alternative for SNP identification using RNA-seq data. The source code and user manuals are available at https://modupeore.github.io/VAP/.
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Affiliation(s)
- Modupeore O. Adetunji
- Department of Animal and Food Sciences, University of Delaware, Newark, Delaware, United States of America
- * E-mail:
| | - Susan J. Lamont
- Department of Animal Science, Iowa State University, Ames, Iowa, United States of America
| | - Behnam Abasht
- Department of Animal and Food Sciences, University of Delaware, Newark, Delaware, United States of America
| | - Carl J. Schmidt
- Department of Animal and Food Sciences, University of Delaware, Newark, Delaware, United States of America
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11
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Genetic lines respond uniquely within the chicken thymic transcriptome to acute heat stress and low dose lipopolysaccharide. Sci Rep 2019; 9:13649. [PMID: 31541148 PMCID: PMC6754502 DOI: 10.1038/s41598-019-50051-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 08/31/2019] [Indexed: 12/16/2022] Open
Abstract
Exposure to high temperatures is known to impair immune functions and disease resistance of poultry. Characterizing changes in the transcriptome can help identify mechanisms by which immune tissues, such as the thymus, respond to heat stress. In this study, 22-day-old chickens from two genetic lines (a relatively resistant Fayoumi line and a more susceptible broiler line) were exposed to acute heat stress (35 °C) and/or immune simulation with lipopolysaccharide (LPS; 100 µg/kg). Transcriptome responses in the thymus were identified by RNA-sequencing (RNA-seq). Expression of most genes was unaffected by heat and/or LPS in the Fayoumi line, whereas these treatments had more impact in the broiler line. Comparisons between the broiler and Fayoumi transcriptomes identified a large number of significant genes both at homeostasis and in response to treatment. Functional analyses predicted that gene expression changes impact immune responses, apoptosis, cell activation, migration, and adhesion. In broilers, acute heat stress changed thymic expression responses to LPS and could impact thymocyte survival and trafficking, and thereby contribute to the negative effects of high temperatures on immune responses. Identification of these genes and pathways provides a foundation for testing targets to improve disease resistance in heat-stressed chickens.
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12
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A Homeostasis Hypothesis of Avian Influenza Resistance in Chickens. Genes (Basel) 2019; 10:genes10070543. [PMID: 31319606 PMCID: PMC6678902 DOI: 10.3390/genes10070543] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 07/04/2019] [Accepted: 07/11/2019] [Indexed: 12/13/2022] Open
Abstract
Avian influenza has caused significant damage to the poultry industry globally. Consequently, efforts have been made to elucidate the disease mechanisms as well as the mechanisms of disease resistance. Here, by investigating two chicken breeds with distinct responses to avian influenza virus (AIV), Leghorn GB2 and Fayoumi M43, we compared their genome, methylation, and transcriptome differences. MX1, HSP90AB1, and HSP90B1 exhibited high degrees of genetic differentiation (FST) between the two species. Except for the MX1-involved direct anti-virus mechanism, we found that at the methylation and transcriptome levels, the more AIV-resistant breed, Fayoumi, exhibited less variation compared with Leghorn after AIV inoculation, which included change trends in differentially expressed regions, top-fold change genes with FDR-corrected p < 0.05, immune response related genes, and housekeeping genes. Fayoumi also showed better consistency regarding changes in methylation and changes at the transcriptome level. Our results suggest a homeostasis hypothesis for avian influenza resistance, with Fayoumi maintaining superior homeostasis at both the epigenetic and gene expression levels. Three candidate genes—MX1, HSP90AB1, and HSP90B1—showed genetic differentiation and altered gene expression, methylation, and protein expression, which merit attention in further functional studies.
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13
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Zhuo Z, Lamont SJ, Abasht B. RNA-Seq Analyses Identify Additivity as the Predominant Gene Expression Pattern in F1 Chicken Embryonic Brain and Liver. Genes (Basel) 2019; 10:genes10010027. [PMID: 30621090 PMCID: PMC6356826 DOI: 10.3390/genes10010027] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/15/2018] [Accepted: 12/21/2018] [Indexed: 12/19/2022] Open
Abstract
The superior performance of hybrids to parents, termed heterosis, has been widely utilized in animal and plant breeding programs, but the molecular mechanism underlying heterosis remains an enigma. RNA-Seq provides a novel way to investigate heterosis at the transcriptome-wide level, because gene expression functions as an intermediate phenotype that contributes to observable traits. Here we compared embryonic gene expression between chicken hybrids and their inbred parental lines to identify inheritance patterns of gene expression. Inbred Fayoumi and Leghorn were crossed reciprocally to obtain F1 fertile eggs. RNA-Seq was carried out using 24 brain and liver samples taken from day 12 embryos, and the differentially expressed (DE) genes were identified by pairwise comparison among the hybrids, parental lines, and mid-parent expression values. Our results indicated the expression levels of the majority of the genes in the F1 cross are not significantly different from the mid-parental values, suggesting additivity as the predominant gene expression pattern in the F1. The second and third prevalent gene expression patterns are dominance and over-dominance. Additionally, we found only 7⁻20% of the DE genes exhibit allele-specific expression in the F1, suggesting that trans regulation is the main driver for differential gene expression and thus contributes to heterosis effect in the F1 crosses.
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Affiliation(s)
- Zhu Zhuo
- Department of Animal and Food Sciences, University of Delaware, Newark, DE 19716, USA.
| | - Susan J Lamont
- Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
| | - Behnam Abasht
- Department of Animal and Food Sciences, University of Delaware, Newark, DE 19716, USA.
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14
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Rowland K, Wolc A, Gallardo RA, Kelly T, Zhou H, Dekkers JCM, Lamont SJ. Genetic Analysis of a Commercial Egg Laying Line Challenged With Newcastle Disease Virus. Front Genet 2018; 9:326. [PMID: 30177951 PMCID: PMC6110172 DOI: 10.3389/fgene.2018.00326] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 07/30/2018] [Indexed: 01/17/2023] Open
Abstract
In low income countries, chickens play a vital role in daily life. They provide a critical source of protein through egg production and meat. Newcastle disease, caused by avian paramyxovirus type 1, has been ranked as the most devastating disease for scavenging chickens in Africa and Asia. High mortality among flocks infected with velogenic strains leads to a devastating loss of dietary protein and buying power for rural households. Improving the genetic resistance of chickens to Newcastle Disease virus (NDV), in addition to vaccination, is a practical target for improvement of poultry production in low income countries. Because response to NDV has a component of genetic control, it can be influenced through selective breeding. Adding genomic information to a breeding program can increase the amount of genetic progress per generation. In this study, we challenged a commercial egg-laying line with a lentogenic strain of NDV, measured phenotypic responses, collected genotypes, and associated genotypes with phenotypes. Collected phenotypes included viral load at 2 and 6 days post-infection (dpi), antibody levels pre-challenge and 10 dpi, and growth rates pre- and post-challenge. Six suggestive QTL associated with response to NDV and/or growth were identified, including novel and known QTL confirming previously reported associations with related traits. Additionally, previous RNA-seq analysis provided support for several of the genes located in or near the identified QTL. Considering the trend of negative genetic correlation between antibody and Newcastle Disease tolerance (growth under disease) and estimates of moderate to high heritability, we provide evidence that these NDV response traits can be influenced through selective breeding. Producing chickens that perform favorably in challenging environments will ultimately increase the supply of quality protein for human consumption.
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Affiliation(s)
- Kaylee Rowland
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Anna Wolc
- Department of Animal Science, Iowa State University, Ames, IA, United States.,Hy-Line International, Dallas Center, IA, United States
| | - Rodrigo A Gallardo
- School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Terra Kelly
- School of Veterinary Medicine, University of California, Davis, Davis, CA, United States.,Department of Animal Science, University of California, Davis, Davis, CA, United States
| | - Huaijun Zhou
- Department of Animal Science, University of California, Davis, Davis, CA, United States
| | - Jack C M Dekkers
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Susan J Lamont
- Department of Animal Science, Iowa State University, Ames, IA, United States
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15
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Deist MS, Lamont SJ. What Makes the Harderian Gland Transcriptome Different From Other Chicken Immune Tissues? A Gene Expression Comparative Analysis. Front Physiol 2018; 9:492. [PMID: 29867543 PMCID: PMC5952037 DOI: 10.3389/fphys.2018.00492] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 04/17/2018] [Indexed: 11/13/2022] Open
Abstract
The Harderian gland is a sparsely characterized immune tissue known to play an important role in local immunity. The function of the Harderian gland, however, is not clearly defined. Measuring the expression of all genes using RNA-seq enables the identification of genes, pathways, or networks of interest. Our relative RNA-seq expression analysis compared the chicken Harderian gland transcriptome to other important primary and secondary immune tissues including the bursa of Fabricius, thymus, and spleen of non-challenged birds. A total of 2,386 transcripts were identified as highly expressed in the Harderian gland. Gene set enrichment showed the importance of G-protein coupled receptor signaling and several immune pathways. Among the genes highly expressed in the Harderian gland were 48 miRNAs, a category of genetic elements involved in regulation of gene expression. Several identified miRNAs have immune related functions. This analysis gives insight to the unique immune processes inherent in the Harderian gland.
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Affiliation(s)
- Melissa S Deist
- Department of Animal Science, Iowa State University, Ames, IA, United States
| | - Susan J Lamont
- Department of Animal Science, Iowa State University, Ames, IA, United States
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16
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Resistant and susceptible chicken lines show distinctive responses to Newcastle disease virus infection in the lung transcriptome. BMC Genomics 2017; 18:989. [PMID: 29281979 PMCID: PMC5745900 DOI: 10.1186/s12864-017-4380-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 12/11/2017] [Indexed: 01/28/2023] Open
Abstract
Background Newcastle disease virus (NDV) is a threat to poultry production worldwide. A better understanding of mechanisms of resistance and susceptibility to this virus will improve measures for NDV prevention and control. Males and females from resistant Fayoumi and susceptible Leghorn lines were either challenged with a lentogenic strain of the virus or given a mock infection at 3 weeks of age. The lung transcriptomes generated by RNA-seq were studied using contrasts across the challenged and nonchallenged birds, the two lines, and three time points post-infection, and by using Weighted Gene Co-expression Network Analysis (WGNCA). Results Genetic line and sex had a large impact on the lung transcriptome. When contrasting the challenged and nonchallenged birds, few differentially expressed genes (DEG) were identified within each line at 2, 6, and 10 days post infection (dpi), except for the more resistant Fayoumi line at 10 dpi, for which several pathways were activated and inhibited at this time. The interaction of challenge and line at 10 dpi significantly impacted 131 genes (False Discovery Rate (FDR) <0.05), one of which was PPIB. Many DEG were identified between the Fayoumi and Leghorns. The number of DEG between the two lines in the challenged birds decreased over time, but increased over time in the nonchallenged birds. The nonchallenged Fayoumis at 10 dpi showed enrichment of immune type cells when compared to 2 dpi, suggesting important immune related development at this age. These changes between 10 and 2 dpi were not identified in the challenged Fayoumis. The energy allocated to host defense may have interrupted normal lung development. WGCNA identified important modules and driver genes within those modules that were associated with traits of interest, several of which had no known associated function. Conclusions The lines’ unique response to NDV offers insights into the potential means of their resistance and susceptibility. The lung transcriptome shows a unique response to lentogenic NDV compared to a previous study on the trachea of the same birds. It is important to analyze multiple tissues in order to best understand the chicken’s overall response to NDV challenge and improve strategies to combat this devastating disease. Electronic supplementary material The online version of this article (10.1186/s12864-017-4380-4) contains supplementary material, which is available to authorized users.
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17
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RNA-Seq Analyses Identify Frequent Allele Specific Expression and No Evidence of Genomic Imprinting in Specific Embryonic Tissues of Chicken. Sci Rep 2017; 7:11944. [PMID: 28931927 PMCID: PMC5607270 DOI: 10.1038/s41598-017-12179-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 09/05/2017] [Indexed: 12/30/2022] Open
Abstract
Epigenetic and genetic cis-regulatory elements in diploid organisms may cause allele specific expression (ASE) – unequal expression of the two chromosomal gene copies. Genomic imprinting is an intriguing type of ASE in which some genes are expressed monoallelically from either the paternal allele or maternal allele as a result of epigenetic modifications. Imprinted genes have been identified in several animal species and are frequently associated with embryonic development and growth. Whether genomic imprinting exists in chickens remains debatable, as previous studies have reported conflicting evidence. Albeit no genomic imprinting has been reported in the chicken embryo as a whole, we interrogated the existence or absence of genomic imprinting in the 12-day-old chicken embryonic brain and liver by examining ASE in F1 reciprocal crosses of two highly inbred chicken lines (Fayoumi and Leghorn). We identified 5197 and 4638 ASE SNPs, corresponding to 18.3% and 17.3% of the genes with a detectable expression in the embryonic brain and liver, respectively. There was no evidence detected of genomic imprinting in 12-day-old embryonic brain and liver. While ruling out the possibility of imprinted Z-chromosome inactivation, our results indicated that Z-linked gene expression is partially compensated between sexes in chickens.
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18
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Fuentes-Pardo AP, Ruzzante DE. Whole-genome sequencing approaches for conservation biology: Advantages, limitations and practical recommendations. Mol Ecol 2017; 26:5369-5406. [PMID: 28746784 DOI: 10.1111/mec.14264] [Citation(s) in RCA: 152] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 06/23/2017] [Accepted: 06/28/2017] [Indexed: 12/14/2022]
Abstract
Whole-genome resequencing (WGR) is a powerful method for addressing fundamental evolutionary biology questions that have not been fully resolved using traditional methods. WGR includes four approaches: the sequencing of individuals to a high depth of coverage with either unresolved or resolved haplotypes, the sequencing of population genomes to a high depth by mixing equimolar amounts of unlabelled-individual DNA (Pool-seq) and the sequencing of multiple individuals from a population to a low depth (lcWGR). These techniques require the availability of a reference genome. This, along with the still high cost of shotgun sequencing and the large demand for computing resources and storage, has limited their implementation in nonmodel species with scarce genomic resources and in fields such as conservation biology. Our goal here is to describe the various WGR methods, their pros and cons and potential applications in conservation biology. WGR offers an unprecedented marker density and surveys a wide diversity of genetic variations not limited to single nucleotide polymorphisms (e.g., structural variants and mutations in regulatory elements), increasing their power for the detection of signatures of selection and local adaptation as well as for the identification of the genetic basis of phenotypic traits and diseases. Currently, though, no single WGR approach fulfils all requirements of conservation genetics, and each method has its own limitations and sources of potential bias. We discuss proposed ways to minimize such biases. We envision a not distant future where the analysis of whole genomes becomes a routine task in many nonmodel species and fields including conservation biology.
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19
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Novel Mechanisms Revealed in the Trachea Transcriptome of Resistant and Susceptible Chicken Lines following Infection with Newcastle Disease Virus. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2017; 24:CVI.00027-17. [PMID: 28331077 PMCID: PMC5424241 DOI: 10.1128/cvi.00027-17] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 03/13/2017] [Indexed: 12/18/2022]
Abstract
Newcastle disease virus (NDV) has a devastating impact on poultry production in developing countries. This study examined the transcriptome of tracheal epithelial cells from two inbred chicken lines that differ in NDV susceptibility after challenge with a high-titer inoculum of lentogenic NDV. The Fayoumi line had a significantly lower NDV load postchallenge than the Leghorn line, demonstrating the Fayoumi line's classification as a relatively NDV-resistant breed. Examination of the trachea transcriptome showed a large increase in immune cell infiltration in the trachea in both lines at all times postinfection. The pathways conserved across lines and at all three time points postinfection included iCOS-iCOSL signaling in T helper cells, NF-κB signaling, the role of nuclear factor of activated T cells in the regulation of the immune response, calcium-induced T lymphocyte apoptosis, phospholipase C signaling, and CD28 signaling in T helper cells. Although shared pathways were seen in the Fayoumi and Leghorn lines, each line showed unique responses as well. The downregulation of collagen and the activation of eukaryotic translation initiation factor 2 signaling in the Fayoumis relative to the Leghorns at 2 days postinfection may contribute to the resistance phenotype seen in the Fayoumis. This study provides a further understanding of host-pathogen interactions which could improve vaccine efficacy and, in combination with genome-wide association studies, has the potential to advance strategies for breeding chickens with enhanced resistance to NDV.
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