De novo assembly of a young Drosophila Y chromosome using single-molecule sequencing and chromatin conformation capture
Fig 6
Karyotype evolution in Drosophila miranda.
A. Chromosome arm homology in D. miranda. Genes in D. miranda are color coded according to their location in D. melanogaster (see Fig 1). B. Sequence composition of the D. miranda dot chromosome. Shown is the origin of dot genes (color coded as in Fig 1), the repeat and H3K9me3 content, as well as the location of sequenced BAC clones. Ppr-Y and kl-3 are genes located on the ancestral Y of Drosophila. C. Origin of the D. miranda Y/neo-Y. Shown are the location of centromeric and telomeric repeats, H3K9me3 enrichments, the color coded location of single-copy neo-Y genes (with black corresponding to unknown ancestral location in D. pseudoobscura), the location of homologous Y-linked genes identified in D. pseudoobscura, mapping of Y-derived sequencing reads from D. pseudoobscura, and the location of the rDNA genes. The inferred ancestry of the Y/neo-Y chromosome is shown as a cartoon, with the short arm presumably corresponding to the Y chromosome shared with D. pseudoobscura and the long arm representing the neo-Y. D. Our genomic analysis allows us to reconstruct sex chromosome evolution in D. miranda (see text). BAC, bacterial artificial chromosome; chr, chromosome; H3K9me3, trimethylation of histone 3 lysine 9; rDNA, ribosomal DNA; Yanc, ancestral Y chromosome.