Reference - Detail
RRC ID | 81003 |
---|---|
Author | Inoue YH, do Carmo Avides M, Shiraki M, Deak P, Yamaguchi M, Nishimoto Y, Matsukage A, Glover DM. |
Title | Orbit, a novel microtubule-associated protein essential for mitosis in Drosophila melanogaster. |
Journal | J Cell Biol |
Abstract |
We describe a Drosophila gene, orbit, that encodes a conserved 165-kD microtubule-associated protein (MAP) with GTP binding motifs. Hypomorphic mutations in orbit lead to a maternal effect resulting in branched and bent mitotic spindles in the syncytial embryo. In the larval central nervous system, such mutants have an elevated mitotic index with some mitotic cells showing an increase in ploidy. Amorphic alleles show late lethality and greater frequencies of hyperploid mitotic cells. The presence of cells in the hypomorphic mutant in which the chromosomes can be arranged, either in a circular metaphase or an anaphase-like configuration on monopolar spindles, suggests that polyploidy arises through spindle and chromosome segregation defects rather than defects in cytokinesis. A role for the Orbit protein in regulating microtubule behavior in mitosis is suggested by its association with microtubules throughout the spindle at all mitotic stages, by its copurification with microtubules from embryonic extracts, and by the finding that the Orbit protein directly binds to MAP-free microtubules in a GTP-dependent manner. |
Volume | 149(1) |
Pages | 153-66 |
Published | 2000-4-3 |
DOI | 10.1083/jcb.149.1.153 |
PMID | 10747094 |
PMC | PMC2175100 |
MeSH | Alleles Amino Acid Sequence Animals Central Nervous System / cytology Central Nervous System / growth & development Chromosomes / genetics Chromosomes / metabolism Conserved Sequence / genetics Drosophila Proteins* Drosophila melanogaster / cytology* Drosophila melanogaster / embryology Drosophila melanogaster / genetics Female Genes, Insect / genetics Guanosine Triphosphate / metabolism Insect Proteins / chemistry Insect Proteins / genetics Insect Proteins / metabolism* Larva / cytology Larva / growth & development Male Microtubule-Associated Proteins / chemistry Microtubule-Associated Proteins / genetics Microtubule-Associated Proteins / metabolism* Microtubules / metabolism* Mitosis* Molecular Sequence Data Mutation / genetics Phenotype Physical Chromosome Mapping Polyploidy RNA, Messenger / analysis RNA, Messenger / genetics Spindle Apparatus / genetics Spindle Apparatus / metabolism |
IF | 8.811 |
Resource | |
Drosophila | DGRC#119172 DGRC#119173 DGRC#119175 |