Project description:In this study, we utilized Comparative Genomic Hybridization (CGH), using probes designed from EST sequence, to identify genes located on the X chromosome of four species in the stalk-eyed fly genus Teleopsis. Analysis of log ratio values from the CGH microarrays for over 3400 genes produces a strongly bimodal distribution that clearly differentiates autosomal from X-linked genes for all four species. Genetic mapping of 35 of these genes in T. dalmanni indicates the CGH results correctly identified chromosomal location in all cases. Syntenic comparison with Drosophila indicates that 90% of the X-linked genes in Teleopsis are homologous to genes located on chromosome 2L in D. melanogaster, suggesting the formation of a nearly complete neo-X chromosome from Muller element B in the Dipteran lineage leading to Teleopsis. Overall, this study demonstrates CGH is a useful technique for identifying chromosomal sex-linkage and should be applicable to other organisms with EST or partial genomic information.
Project description:We utilized Comparative Genomic Hybridization (CGH), using probes designed from de novo assembly of a testes transcriptome, to identify genes located on the sex chromosomes and autosomes of a stalk-eyed fly, Teleopsis quinqueguttata. Analysis of X chromosome gene content revealed the evolution of a neo-X chromosome that originated prior to the diversification of the family. Comparison of X-linkage across three species spanning the phylogenetic breadth of the family indicates abundant chromosomal gene movement, particularly for genes expressed exclusively in the testes.
Project description:In this study, we utilized Comparative Genomic Hybridization (CGH), using probes designed from EST sequence, to identify genes located on the X chromosome of four species in the stalk-eyed fly genus Teleopsis. Analysis of log ratio values from the CGH microarrays for over 3400 genes produces a strongly bimodal distribution that clearly differentiates autosomal from X-linked genes for all four species. Genetic mapping of 35 of these genes in T. dalmanni indicates the CGH results correctly identified chromosomal location in all cases. Syntenic comparison with Drosophila indicates that 90% of the X-linked genes in Teleopsis are homologous to genes located on chromosome 2L in D. melanogaster, suggesting the formation of a nearly complete neo-X chromosome from Muller element B in the Dipteran lineage leading to Teleopsis. Overall, this study demonstrates CGH is a useful technique for identifying chromosomal sex-linkage and should be applicable to other organisms with EST or partial genomic information. Two-condition experiment, female vs. male DNA, for four species, each with 4 biological replicates
Project description:We utilized Comparative Genomic Hybridization (CGH), using probes designed from de novo assembly of a testes transcriptome, to identify genes located on the sex chromosomes and autosomes of a stalk-eyed fly, Teleopsis quinqueguttata. Analysis of X chromosome gene content revealed the evolution of a neo-X chromosome that originated prior to the diversification of the family. Comparison of X-linkage across three species spanning the phylogenetic breadth of the family indicates abundant chromosomal gene movement, particularly for genes expressed exclusively in the testes. Two-condition experiment, female vs. male DNA, for one species with 3 biological replicates
Project description:Comparative Genomic Hybridization (CGH) reveals sex chromosome location and gene movement in stalk-eyed flies (family Diopsidae), Teleopsis quinqueguttata
