title: Identification of a putative DEAD-box RNA helicase and a zinc-finger protein in Candida albicans by functional complementation of the S. cerevisiae rok1 mutation.
abstract: We identified two novel genes, CHR1 and CSR1, of the fungal pathogen Candida albicans, by functional complementation of the Saccharomyces cerevisiae rok1 mutation. The Rok1 protein is a member of the DEAD protein family of ATP-dependent RNA helicases. ROK1 is required for cell cycle progression and also for rRNA processing. The CHR1 gene product of 578 amino acids is highly homologous to the Rok1 protein (54% identity) and is considered to be a putative DEAD-box RNA helicase. We predict that the CSR1 gene encodes a 73 kDa protein of 612 amino acids with five zinc-finger motifs at the C-terminal region. CHR1 or CSR1 on a high-copy number plasmid showed a slow-growth phenotype in a condition where the ROK1 expression is turned on from the GAL1 promoter. This result is consistent with the lethality caused by the ROK1 overexpression. We conclude that CHR1 encodes a functional homologue of Rok1 protein and CSR1 is a heterologous suppressor of the rok1 mutation.
authors.affiliation: Department of Microbiology, College of Natural Sciences, Chungnam National University, Taejeon 305-764, South Korea.
authors.forename: W I
authors.initials: WI
authors.lastname: Kim
authors.forename: W B
authors.initials: WB
authors.lastname: Lee
authors.forename: K
authors.initials: K
authors.lastname: Song
authors.forename: J
authors.initials: J
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002176:Candida albicans / Q000201:enzymology / Q000235:genetics*; D002503:Centromere / Q000235:genetics; D053487:DEAD-box RNA Helicases; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D005656:Fungal Proteins / Q000235:genetics; D005800:Genes, Fungal / Q000235:genetics; D005816:Genetic Complementation Test; D005822:Genetic Vectors; D008969:Molecular Sequence Data; D009154:Mutation; D020365:RNA Helicases / Q000235:genetics*; D012097:Repressor Proteins; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013489:Suppression, Genetic; D016335:Zinc Fingers / Q000235:genetics*
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D012097:Repressor Proteins; C408523:SUR1 protein, Candida albicans; D029701:Saccharomyces cerevisiae Proteins; C120858:ROK1 protein, S cerevisiae; D053487:DEAD-box RNA Helicases; D020365:RNA Helicases