Project description:Marek’s disease (MD) is a viral neoplastic disease in chickens caused by the MD virus (MDV). Successful vaccination strategies against MD have resulted in a progressive increase in the virulence of MDV and therefore, the understanding of genetic resistance to MD is considered crucial to the long-term control of the disease. Here we examine whether MDV infection induces changes in the epigenetic status of genes and whether this response is dependent on the host genotype. We generated genome-wide histone 3 lysine 4 (H3K4) and histone 3 lysine 27 (H3K27) trimethylation maps in thymus tissues from chicken lines with varying resistance to MD. Differential chromatin marks were observed on several genes previously implicated in MD such as MX1, MMP2 and CTLA-4 and also on novel genes such as EAF2, IGF2BP1 and GAL. We also detected bivalent domains on transcriptional regulators such as BCL6, CITED2 and EGR1 that have particular functions in immune response. Moreover, novel putative roles for GAL and CITED2 in the mechanism of MD progression were uncovered. We also found tissue-specific effects of MDV infection with certain genes exhibiting differential marks only in spleen. Our results suggest widespread epigenetic changes are induced by MDV infection extent of which is determined by the level of MD resistance of the host. 8 samples examined: 2 histone modifications X 2 chicken lines with varying resistance to MD X 2 groups - infected and control.
Project description:Copy number variation profiles comparing control female Dehong chiken blood DNA with 11 different chicken breeds(Silkie, Tibetan Chicken, Gallus gallus spadiceus, Bearded Chicken, Jinhu Chicken, Anak Chicken, Beijing Fatty Chicken, Langshan Chicken, Qingyuan partridge Chicken, Shek-Ki Chicken, Wenchang Chicken) blood DNA. Each test breeds had one male and one female sample, totally 22 test DNA samples.Goal is to get the golbal copy number variation profile between chicken breeds.
Project description:Copy number variation profiles comparing control female Dehong chicken blood DNA with 3 different chicken breeds (white Leghorn, Cobb broiler, and Dou chicken) blood DNA. Each test breed had one male and one female sample, for a total of 6 test DNA samples. The goal is to determine the global copy number variation profiles between chicken breeds.
Project description:Adaptation to hypoxia is a complicated and important physiological course for organisms, but the genetic mechanism underlying the adaptation is not fully understood yet. Tibetan Chicken (T), an indigenous chicken breed in China which inhabit in high areas with an altitude above 2,900 meters. Shouguang Chicken(S) and Dwarf Recessive White Chicken (DRW), two lowland chicken breeds, were used as control groups. The heart was the first functional organ to develop during the embryonic development. Furthermore, the heart is an efficient energy converter utilizing the most appropriate fuel for a given environment. Therefore, GeneChip® Chicken Genome Array was employed to identify the differentially expressed genes in embryonic hearts of Tibetan Chicken and two lowland chicken breeds in both hypoxic and normoxic incubating environments with a genome wide profile. Keywords: stress response
Project description:The conservation and development of chicken has considerably affected human activities, but the admixture history of chicken breeds has so far been poorly demonstrated especially for Chinese indigenous breeds. Using genotypes from 580961 single nucleotide polymorphism markers scored in 1201 animals, we evaluate the genetic diversity (heterozygosity and proportion of polymorphic markers), Linkage disequilibrium (LD) decay, population structure (principal component analysis and neighbor-joining tree), genetic differentiation (FST and genetic distance) and migration events (Treemix and f-statistics) of eight domesticated chicken breeds. All population analytical methods reveal patterns of hybridization which occurred after divergence in Tibetan chicken. We argue that chicken migration and admixture followed by trade have been important forces in shaping modern Chinese chicken genomic variation. Moreover, isolation by distance may play critical role in the shaping genomic variation within Eurasia continent chicken breeds.
Project description:We compared gene expression in oviduct tissues between unmated (control) and mated hen. As spermatozoa are foreign to the female reproductive tract therefore we were interested to look at how spermatozoa survive in the female reproductive tract and keep their fertilization potentiality. To check that we collected tissues from oviduct of both control and mated female chicken and compared if sperm deposition to the oviduct made any gene expression shift related to sperm survival.
Project description:Adaptation to hypoxia is a complicated and important physiological course for organisms, but the genetic mechanism underlying the adaptation is not fully understood yet. Tibetan Chicken (T), an indigenous chicken breed in China which inhabit in high areas with an altitude above 2,900 meters. Shouguang Chicken(S) and Dwarf Recessive White Chicken (DRW), two lowland chicken breeds, were used as control groups. The heart was the first functional organ to develop during the embryonic development. Furthermore, the heart is an efficient energy converter utilizing the most appropriate fuel for a given environment. Therefore, GeneChip® Chicken Genome Array was employed to identify the differentially expressed genes in embryonic hearts of Tibetan Chicken and two lowland chicken breeds in both hypoxic and normoxic incubating environments with a genome wide profile. Experiment Overall Design: To obtain general expression profiles of embryonic hearts in Tibetan Chicken(T), Dwarf Recessive White Chicken (DRW)and Shouguang Chicken (S)in hypoxia and normoxia, the fertilized full sib eggs of all the three chicken breeds were incubated under two different conditions. The heart was isolated from all the three chicken breeds under the two different conditions for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Since Japanese quail and chicken belong to the same order Galliforms, DNA sequence of both species are highly conserved and proved to be applicable for various analyses each other. Quail are commonly used to address physiological questions for reasons of economy. To test whether chicken microarrays are useful to quail samples, we compared hybridization signals of chicken and quail genomic DNA on Affymetrix chicken genome array. Keywords: comparative genomic hybridization
Project description:Gonadal sex differentiation – testis versus ovary formation – is a fundamental process required for reproduction and evolution. Reflecting this importance, the embryonic gonads of vertebrate species comprise the same key cell types; germ cells, supporting cells and interstitial steroidogenic cells. Remarkably, the genetic triggers for gonadal sex differentiation vary across species (the SRY gene in mammals, DMRT1 in birds and some turtles, temperature in many reptiles, AMH and various other genes in fishes). Despite this variation, the cell biology of gonadal development was long thought to be largely conserved. Here, we present a comprehensive analysis of gonadal sex differentiation, using the chicken embryo as a model and considering the entire gonad. We sampled over 30,000 cells across several developmental stages, prior, during and after the onset of gonadal sex differentiation. The data provide several new insights into cell lineage specification during vertebrate gonadogenesis. Combining lineage tracing with single cell transcriptomics, the data show that somatic supporting cells of the embryonic chicken gonad do not derive from the coelomic epithelium, in contrast to other vertebrates studied. Instead, the early somatic precursors cells of the gonads in both sexes derive from a DMRT1+/PAX2+/WNT4+/OSR1+ mesenchymal cell population. In particular, PAX2 marks immigrating mesenchymal cells that give rise to the supporting cell lineage. We find a greater complexity of gonadal cell types than previously thought, including the identification of two distinct sub-populations of Sertoli cells in developing testes, and derivation of embryonic steroidogenic cells from a differentiated supporting cell lineage. We provide significantly improved resolution of gonadal cell types and identify several new gonadal marker genes. Altogether, these results indicate that, just as the genetic trigger for sex differs across vertebrate groups, cell lineage specification in the gonad may also vary substantially.