title: The germline stem cells of Drosophila melanogaster partition DNA non-randomly.
abstract: The Immortal Strand Hypothesis proposes that asymmetrically dividing stem cells cosegregate chromatids to retain ancestral DNA templates. Using both pulse-chase and label retention assays, we show that non-random partitioning of DNA occurs in germline stem cells (GSCs) in the Drosophila ovary as these divide asymmetrically to generate a new GSC and a differentiating cystoblast. This process is disrupted when GSCs are forced to differentiate through the overexpression of Bag of Marbles, a factor that impels the terminal differentiation of cystoblasts. When Decapentaplegic, a ligand which maintains the undifferentiated state of GSCs, is expressed ectopically the non-random partitioning of DNA is similarly disrupted. Our data suggest asymmetric chromatid segregation is coupled to mechanisms specifying cellular differentiation via asymmetric stem cell division.
authors.affiliation: Department of Medical Genetics and Microbiology, University of Toronto, 160 College Street, Toronto, Ontario, Canada M5S 3E1. phillip.karpowicz@utoronto.ca
authors.forename: Phillip
authors.initials: P
authors.lastname: Karpowicz
authors.forename: Milena
authors.initials: M
authors.lastname: Pellikka
authors.forename: Evelyn
authors.initials: E
authors.lastname: Chea
authors.forename: Dorothea
authors.initials: D
authors.lastname: Godt
authors.forename: Ulrich
authors.initials: U
authors.lastname: Tepass
authors.forename: Derek
authors.initials: D
authors.lastname: van der Kooy
mesh_terms: D000818:Animals; D002455:Cell Division / Q000502:physiology*; D004247:DNA / Q000235:genetics / Q000378:metabolism*; D004261:DNA Replication; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster / Q000166:cytology / Q000235:genetics; D005260:Female; D010053:Ovary / Q000166:cytology; D013234:Stem Cells / Q000166:cytology / Q000502:physiology*
chemical_list: D029721:Drosophila Proteins; D004247:DNA