title: Systematic yeast synthetic lethal and synthetic dosage lethal screens identify genes required for chromosome segregation.
abstract: Accurate chromosome segregation requires the execution and coordination of many processes during mitosis, including DNA replication, sister chromatid cohesion, and attachment of chromosomes to spindle microtubules via the kinetochore complex. Additional pathways are likely involved because faithful chromosome segregation also requires proteins that are not physically associated with the chromosome. Using kinetochore mutants as a starting point, we have identified genes with roles in chromosome stability by performing genome-wide screens employing synthetic genetic array methodology. Two genetic approaches (a series of synthetic lethal and synthetic dosage lethal screens) isolated 211 nonessential deletion mutants that were unable to tolerate defects in kinetochore function. Although synthetic lethality and synthetic dosage lethality are thought to be based upon similar genetic principles, we found that the majority of interactions associated with these two screens were nonoverlapping. To functionally characterize genes isolated in our screens, a secondary screen was performed to assess defects in chromosome segregation. Genes identified in the secondary screen were enriched for genes with known roles in chromosome segregation. We also uncovered genes with diverse functions, such as RCS1, which encodes an iron transcription factor. RCS1 was one of a small group of genes identified in all three screens, and we used genetic and cell biological assays to confirm that it is required for chromosome stability. Our study shows that systematic genetic screens are a powerful means to discover roles for uncharacterized genes and genes with alternative functions in chromosome maintenance that may not be discovered by using proteomics approaches.
authors.affiliation: Wine Research Centre and Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada V6T 1Z4.
authors.forename: Vivien
authors.initials: V
authors.lastname: Measday
authors.forename: Kristin
authors.initials: K
authors.lastname: Baetz
authors.forename: Julie
authors.initials: J
authors.lastname: Guzzo
authors.forename: Karen
authors.initials: K
authors.lastname: Yuen
authors.forename: Teresa
authors.initials: T
authors.lastname: Kwok
authors.forename: Bilal
authors.initials: B
authors.lastname: Sheikh
authors.forename: Huiming
authors.initials: H
authors.lastname: Ding
authors.forename: Ryo
authors.initials: R
authors.lastname: Ueta
authors.forename: Trinh
authors.initials: T
authors.lastname: Hoac
authors.forename: Benjamin
authors.initials: B
authors.lastname: Cheng
authors.forename: Isabelle
authors.initials: I
authors.lastname: Pot
authors.forename: Amy
authors.initials: A
authors.lastname: Tong
authors.forename: Yuko
authors.initials: Y
authors.lastname: Yamaguchi-Iwai
authors.forename: Charles
authors.initials: C
authors.lastname: Boone
authors.forename: Phil
authors.initials: P
authors.lastname: Hieter
authors.forename: Brenda
authors.initials: B
authors.lastname: Andrews
mesh_terms: D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / Q000378:metabolism; D043171:Chromosomal Instability / Q000235:genetics; D020090:Chromosome Segregation / Q000235:genetics*; D015825:Chromosomes, Fungal / Q000378:metabolism; D005800:Genes, Fungal; D005804:Genes, Lethal; D023281:Genomics / Q000379:methods; D018386:Kinetochores / Q000378:metabolism; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000032:analysis / Q000235:genetics / Q000378:metabolism
chemical_list: C090297:AFT1 protein, S cerevisiae; D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; C064042:CBF1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors