title: Phenotypic characterization of Drosophila ida mutants: defining the role of APC5 in cell cycle progression.
abstract: We have cloned and characterized the ida gene that is required for proliferation of imaginal disc cells during Drosophila development. IDA is homologous to APC5, a subunit of the anaphase-promoting complex (APC/cyclosome). ida mRNA is detected in most cell types throughout development, but it accumulates to its highest levels during early embryogenesis. A maternal component of IDA is required for the production of eggs and viable embryos. Homozygous ida mutants display mitotic defects: they die during prepupal development, lack all mature imaginal disc structures, and have abnormally small optic lobes. Cytological observations show that ida mutant brains have a high mitotic index and many imaginal cells contain an aneuploid number of aberrant overcondensed chromosomes. However, cells are not stalled in metaphase, as mitotic stages in which chromosomes are orientated at the equatorial plate are never observed. Interestingly, some APC/C-target substrates such as cyclin B are not degraded in ida mutants, whereas others controlling sister-chromatid separation appear to be turned over. Taken together, these results suggest a model in which IDA/APC5 controls regulatory subfunctions of the anaphase-promoting complex.
authors.affiliation: Department of Molecular Pharmacology and Biological Chemistry, Robert H. Lurie Comprehensive Cancer Center, Northwestern University, 303 East Chicago Avenue, Chicago, IL 60611-3093, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Bentley
authors.forename: Byron C
authors.initials: BC
authors.lastname: Williams
authors.forename: Michael L
authors.initials: ML
authors.lastname: Goldberg
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Andres
mesh_terms: D064173:Anaphase-Promoting Complex-Cyclosome; D000782:Aneuploidy; D000818:Animals; D064193:Apc5 Subunit, Anaphase-Promoting Complex-Cyclosome; D002453:Cell Cycle / Q000235:genetics*; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000302:isolation & purification*; D002869:Chromosome Aberrations; D020090:Chromosome Segregation / Q000235:genetics; D003001:Cloning, Molecular; D019926:Cyclin B / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics* / Q000302:isolation & purification*; D004331:Drosophila melanogaster / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D005804:Genes, Lethal / Q000502:physiology; D018816:Genes, cdc / Q000502:physiology; D007814:Larva / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D008025:Ligases / Q000235:genetics* / Q000378:metabolism; D008675:Metamorphosis, Biological / Q000235:genetics; D008940:Mitotic Index; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D043743:Ubiquitin-Protein Ligase Complexes
chemical_list: D064193:Apc5 Subunit, Anaphase-Promoting Complex-Cyclosome; D018797:Cell Cycle Proteins; C503698:CycB protein, Drosophila; D019926:Cyclin B; D029721:Drosophila Proteins; C577379:Ida protein, Drosophila; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D008025:Ligases