A highly conserved centrosomal kinase, AIR-1, is required for accurate cell cycle progression and segregation of developmental factors in Caenorhabditis elegans embryos.
S. cerevisiae Ipl1, Drosophila Aurora, and the mammalian centrosomal protein IAK-1 define a new subfamily of serine/threonine kinases that regulate chromosome segregation and mitotic spindle dynamics. Mutations in ipl1 and aurora result in the generation of severely aneuploid cells and, in the case of aurora, monopolar spindles arising from a failure in centrosome separation. Here we show that a related, essential protein from C. elegans, AIR-1 (Aurora/Ipl1 related), is localized to mitotic centrosomes. Disruption of AIR-1 protein expression in C. elegans embryos results in severe aneuploidy and embryonic lethality. Unlike aurora mutants, this aneuploidy does not arise from a failure in centrosome separation. Bipolar spindles are formed in the absence of AIR-1, but they appear to be disorganized and are nucleated by abnormal-looking centrosomes. In addition to its requirement during mitosis, AIR-1 may regulate microtubule-based developmental processes as well. Our data suggests AIR-1 plays a role in P-granule segregation and the association of the germline factor PIE-1 with centrosomes.
Cell Biology of Development and Differentiation Group, Developmental Signal Transduction Group, ABL-Basic Research Program, National Cancer Institute-Frederick Cancer Research and Development Center, PO Box B, Frederick, MD 21702, USA.
J M
JM
Schumacher
N
N
Ashcroft
P J
PJ
Donovan
A
A
Golden
D000595:Amino Acid Sequence; D000782:Aneuploidy; D000818:Animals; D064096:Aurora Kinase A; D064127:Aurora Kinases; D017173:Caenorhabditis elegans / Q000196:embryology / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins; D002453:Cell Cycle; D016764:Cell Polarity; D018385:Centrosome / Q000201:enzymology*; D002843:Chromatin / Q000473:pathology; D020090:Chromosome Segregation; D017124:Conserved Sequence; D005455:Fluorescent Antibody Technique; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009687:Nuclear Proteins; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000302:isolation & purification; D017386:Sequence Homology, Amino Acid; D008941:Spindle Apparatus / Q000473:pathology
D029742:Caenorhabditis elegans Proteins; D002843:Chromatin; D009687:Nuclear Proteins; C100950:pie-1 protein, C elegans; D064096:Aurora Kinase A; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases; C576939:air-1 protein, C elegans