Ctf19p: A novel kinetochore protein in Saccharomyces cerevisiae and a potential link between the kinetochore and mitotic spindle.
A genetic synthetic dosage lethality (SDL) screen using CTF13 encoding a known kinetochore protein as the overexpressed reference gene identified two chromosome transmission fidelity (ctf) mutants, YCTF58 and YCTF26. These mutant strains carry independent alleles of a novel gene, which we have designated CTF19. In light of its potential role in kinetochore function, we have cloned and characterized the CTF19 gene in detail. CTF19 encodes a nonessential 369-amino acid protein. ctf19 mutant strains display a severe chromosome missegregation phenotype, are hypersensitive to benomyl, and accumulate at G2/M in cycling cells. CTF19 genetically interacts with kinetochore structural mutants and mitotic checkpoint mutants. In addition, ctf19 mutants show a defect in the ability of centromeres on minichromosomes to bind microtubules in an in vitro assay. In vivo cross-linking and chromatin immunoprecipitation demonstrates that Ctf19p specifically interacts with CEN DNA. Furthermore, Ctf19-HAp localizes to the nuclear face of the spindle pole body and genetically interacts with a spindle-associated protein. We propose that Ctf19p is part of a macromolecular kinetochore complex, which may function as a link between the kinetochore and the mitotic spindle.
Hyland
K M
KM
The Johns Hopkins University School of Medicine, Department of Molecular Biology and Genetics, Baltimore, Maryland 21205, USA.
Kingsbury
J
J
Koshland
D
D
Hieter
P
P
D000705:Anaphase; D003001:Cloning, Molecular; D004271:DNA, Fungal / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D005800:Genes, Fungal; D018386:Kinetochores / Q000737:chemistry*; D046911:Macromolecular Substances; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D008870:Microtubules / Q000737:chemistry / Q000648:ultrastructure; D008938:Mitosis / Q000187:drug effects; D010641:Phenotype; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000187:drug effects / Q000235:genetics; D008941:Spindle Apparatus / Q000737:chemistry*
D004271:DNA, Fungal; D005656:Fungal Proteins; D046911:Macromolecular Substances; D008869:Microtubule-Associated Proteins