Identification and functional characterization of Candida albicans CDC4.
The CDC4 gene of Saccharomyces cerevisiae encodes an essential function that is required for G1-S and G2-M transitions during mitosis and at various stages during meiosis. We have isolated a functional homologue of CDC4 (CaCDC4) from the pathogenic yeast Candida albicans by complementing the S. cerevisiae cdc4-3 mutation with CaCDC4 expressed from its own promoter on a single-copy vector. The predicted product of CaCDC4 has 37% overall identity to the S. cerevisiae Cdc4 protein, although this identity is biased towards the C-terminal region of the two proteins which contains eight copies of the degenerate WD-40 motif, an element found in proteins that regulate diverse biological processes and an F-box domain proximal to the first iteration of the WD-40 motif. Both the F-box domain and WD-40 motifs appear necessary for the mitotic functions of Cdc4 in both yeasts. In contrast to its conserved role in mitosis, C. albicans CDC4 is unable to rescue the meiotic deficiency in a S. cerevisiae cdc4 homozygous diploid under restrictive conditions, even when expressed from an efficient S. cerevisiae promoter. In opposition to S. cerevisiae CDC4 being essential, C. albicans CDC4 appears to be nonessential and in its absence is critical for filamentous growth in C. albicans.
Shieh
Jia-Ching
JC
Department of Life Sciences, Chung Shan Medical University, No. 110, Sec. 1, Janguo N. Road, Taichung City, Taiwan, 40242, ROC. jcs@csmu.edu.tw
White
Anne
A
Cheng
Yu-Che
YC
Rosamond
John
J
D000483:Alleles; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D002176:Candida albicans / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000378:metabolism*; D003001:Cloning, Molecular; D003470:Culture Media / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004262:DNA Restriction Enzymes / Q000378:metabolism; D019143:Evolution, Molecular; D044783:F-Box Proteins / Q000378:metabolism*; D015723:Gene Library; D005816:Genetic Complementation Test; D005821:Genetic Techniques; D016678:Genome; D008540:Meiosis; D008938:Mitosis; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation; D009693:Nucleic Acid Hybridization; D016366:Open Reading Frames; D011401:Promoter Regions, Genetic; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D013696:Temperature; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*
C080443:CDC4 protein, S cerevisiae; D018797:Cell Cycle Proteins; D003470:Culture Media; D044783:F-Box Proteins; D029701:Saccharomyces cerevisiae Proteins; D012313:RNA; D004247:DNA; D044767:Ubiquitin-Protein Ligases; D004262:DNA Restriction Enzymes