title: Birth of a new gene on the Y chromosome of Drosophila melanogaster.
abstract: Contrary to the pattern seen in mammalian sex chromosomes, where most Y-linked genes have X-linked homologs, the Drosophila X and Y chromosomes appear to be unrelated. Most of the Y-linked genes have autosomal paralogs, so autosome-to-Y transposition must be the main source of Drosophila Y-linked genes. Here we show how these genes were acquired. We found a previously unidentified gene (flagrante delicto Y, FDY) that originated from a recent duplication of the autosomal gene vig2 to the Y chromosome of Drosophila melanogaster. Four contiguous genes were duplicated along with vig2, but they became pseudogenes through the accumulation of deletions and transposable element insertions, whereas FDY remained functional, acquired testis-specific expression, and now accounts for ∼20% of the vig2-like mRNA in testis. FDY is absent in the closest relatives of D. melanogaster, and DNA sequence divergence indicates that the duplication to the Y chromosome occurred ∼2 million years ago. Thus, FDY provides a snapshot of the early stages of the establishment of a Y-linked gene and demonstrates how the Drosophila Y has been accumulating autosomal genes.
authors.affiliation: Departamento de Genética, Universidade Federal do Rio de Janeiro, Caixa Postal 68011, 21941-971, Rio de Janeiro, Brazil; bernardo@biologia.ufrj.br ac347@cornell.edu.
authors.forename: Antonio Bernardo
authors.initials: AB
authors.lastname: Carvalho
authors.affiliation: Departamento de Genética, Universidade Federal do Rio de Janeiro, Caixa Postal 68011, 21941-971, Rio de Janeiro, Brazil; Institute of Science and Technology Austria, A-3400 Klosterneuburg, Austria;
authors.forename: Beatriz
authors.initials: B
authors.lastname: Vicoso
authors.affiliation: Departamento de Genética, Universidade Federal do Rio de Janeiro, Caixa Postal 68011, 21941-971, Rio de Janeiro, Brazil;
authors.forename: Claudia A M
authors.initials: CA
authors.lastname: Russo
authors.affiliation: Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853.
authors.forename: Bonnielin
authors.initials: B
authors.lastname: Swenor
authors.affiliation: Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853 bernardo@biologia.ufrj.br ac347@cornell.edu.
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Clark
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D059006:Chromosomes, Insect / Q000235:genetics; D029721:Drosophila Proteins / Q000145:classification / Q000235:genetics; D004331:Drosophila melanogaster / Q000235:genetics*; D005260:Female; D020440:Gene Duplication; D015870:Gene Expression; D017344:Genes, Insect / Q000235:genetics*; D050173:Genes, Y-Linked / Q000235:genetics*; D054643:INDEL Mutation; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014960:X Chromosome / Q000235:genetics; D014998:Y Chromosome / Q000235:genetics*
chemical_list: D029721:Drosophila Proteins; C000605832:FDY protein, Drosophila
keywords: Drosophila melanogaster; FDY; PacBio; Y chromosome; vig2