title: Control of G1 in the developing Drosophila eye: rca1 regulates Cyclin A.
abstract: In the developing eye of Drosophila melanogaster, cells become synchronized in the G1 phase of the cell cycle just prior to the onset of cellular differentiation and morphogenesis. In roughex (rux) mutants, cells enter S phase precociously because of ectopic activation of a Cyclin A/Cdk complex in early G1. This leads to defects in cell fate and pattern formation, and results in abnormalities in the morphology of the adult eye. A screen for dominant suppressors of the rux eye phenotype led to the identification of mutations in cyclin A, string (cdc25), and new cell cycle genes. One of these genes, regulator of cyclin A (rca1), encodes a novel protein required for both mitotic and meiotic cell cycle progression. rca1 mutants arrest in G2 of embryonic cell cycle 16 with a phenotype very similar to cyclin A loss of function mutants. Expression of rca1 transgenes in G1 or in postmitotic neurons promotes Cyclin A protein accumulation and drives cells into S phase in a Cyclin A-dependent fashion.
authors.affiliation: Department of Biological Chemistry, Molecular Biology Institute, University of California, Los Angeles 90095, USA.
authors.forename: X
authors.initials: X
authors.lastname: Dong
authors.forename: K H
authors.initials: KH
authors.lastname: Zavitz
authors.forename: B J
authors.initials: BJ
authors.lastname: Thomas
authors.forename: M
authors.initials: M
authors.lastname: Lin
authors.forename: S
authors.initials: S
authors.lastname: Campbell
authors.forename: S L
authors.initials: SL
authors.lastname: Zipursky
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002453:Cell Cycle / Q000235:genetics / Q000502:physiology; D002454:Cell Differentiation / Q000235:genetics*; D016213:Cyclins / Q000235:genetics* / Q000494:pharmacology; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000378:metabolism*; D005123:Eye / Q000254:growth & development*; D005136:Eye Proteins / Q000235:genetics; D016193:G1 Phase / Q000235:genetics / Q000502:physiology*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D005809:Genes, Regulator / Q000235:genetics; D005820:Genetic Testing; D006651:Histocytochemistry; D007150:Immunohistochemistry; D008969:Molecular Sequence Data; D017421:Sequence Analysis; D013489:Suppression, Genetic / Q000235:genetics
chemical_list: D016213:Cyclins; D029721:Drosophila Proteins; D005136:Eye Proteins; C088084:rux protein, Drosophila