title: An SMC-domain protein in fission yeast links telomeres to the meiotic centrosome.
abstract: Abnormal centrosomal structures similar to those occurring in human cancers are induced in fission yeast by overexpression of the pericentrin homolog Pcp1p. Analysis of abnormal Pcp1p-containing structures with quantitative mass spectrometry and isotope-coded affinity tags identified a coiled-coil, structural maintenance of chromosomes (SMC) domain protein. This protein, termed Ccq1p (coiled-coil protein quantitatively enriched), localizes with Taz1p to telomeres in normal vegetative cells. Fluorescence resonance energy transfer (FRET) measurements indicate that Ccq1p also interacts with centrosomal Pcp1p in mating pheromone-stimulated cells containing centrosomally clustered telomeres. We provide evidence that the Ccq1p-Pcp1p interaction, while essential for meiosis, is deleterious when forced to occur during vegetative growth. Cells lacking one ccq1 allele exhibit a loss-of-function phenotype including abnormally long cell length, chromosome segregation failure, telomeric shortening, and defective telomeric clustering during meiotic prophase. Our data indicate a mechanism underlying meiotic chromosomal bouquet formation and suggest a recruitment model for supernumerary centrosome toxicity.
authors.affiliation: Institute for Systems Biology, Seattle, Washington 98103, USA.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Flory
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Carson
authors.forename: Eric G
authors.initials: EG
authors.lastname: Muller
authors.forename: Ruedi
authors.initials: R
authors.lastname: Aebersold
mesh_terms: D000483:Alleles; D002467:Cell Nucleus / Q000378:metabolism; D018385:Centrosome / Q000378:metabolism*; D015825:Chromosomes, Fungal; D031541:Fluorescence Resonance Energy Transfer; D013058:Mass Spectrometry; D008540:Meiosis; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D008958:Models, Molecular; D020411:Oligonucleotide Array Sequence Analysis; D016366:Open Reading Frames; D010449:Peptide Mapping; D010957:Plasmids; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D012568:Schizosaccharomyces / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D029702:Schizosaccharomyces pombe Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D016615:Telomere / Q000378:metabolism*; D034501:Telomere-Binding Proteins / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D029702:Schizosaccharomyces pombe Proteins; D034501:Telomere-Binding Proteins; C104344:taz1 protein, S pombe