title: A fruitless upstream region that defines the species specificity in the male-specific muscle patterning in Drosophila.
abstract: The muscle of Lawrence (MOL) is a male-specific muscle present in the abdomen of some adult Drosophila species. Formation of the MOL depends on innervation by motoneurons that express fruitless, a neural male determinant. Drosophila melanogaster males carry a pair of MOLs in the 5th abdominal segment, whereas D. subobscura males carry a pair in both the 5th and 4th segments. We hypothesized that the fru gene of D. subobscura but not that of D. melanogaster contains a cis element that directs the formation of the additional pair of MOLs. Successively extended 5' DNA fragments to the P1 promoter of D. subobscura or the corresponding fragments that are chimeric (i.e., containing both melanogaster and subobscura elements) were introduced into D. melanogaster and tested for their ability to induce the MOL to locate the hypothetical cis element. We found that a 1.5-2-kb genomic fragment located 4-6-kb upstream of the P1 promoter in D. subobscura but not that of D. melanogaster permits MOL formation in females, provided this fragment is grafted to the distal ∼4-kb segment from D. melanogaster, demonstrating that this genomic fragment of D. subobscura contains a cis element for the MOL induction.
authors.affiliation: Division of Neurogenetics, Tohoku University Graduate School of Life Sciences , Sendai , Japan.
authors.forename: Sakino
authors.initials: S
authors.lastname: Takayanagi
authors.forename: Gakuta
authors.initials: G
authors.lastname: Toba
authors.forename: Tamas
authors.initials: T
authors.lastname: Lukacsovich
authors.forename: Manabu
authors.initials: M
authors.lastname: Ote
authors.forename: Kosei
authors.initials: K
authors.lastname: Sato
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yamamoto
mesh_terms: D000009:Abdominal Muscles / Q000378:metabolism*; D000818:Animals; D030801:Animals, Genetically Modified; D029721:Drosophila Proteins / Q000235:genetics*; D004331:Drosophila melanogaster; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics*; D008297:Male; D009419:Nerve Tissue Proteins / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012737:Sex Factors; D013045:Species Specificity; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D029721:Drosophila Proteins; D009419:Nerve Tissue Proteins; D014157:Transcription Factors; C103226:fru protein, Drosophila
keywords: D. subobscura; Evolution; enhancers; neuromuscular system; sex determination gene