Functional equivalence of translation factor eIF5B from Candida albicans and Saccharomyces cerevisiae.
Eukaryotic translation initiation factor 5B (eIF5B) plays a role in recognition of the AUG codon in conjunction with translation factor eIF2, and promotes joining of the 60S ribosomal subunit. To see whether the eIF5B proteins of other organisms function in Saccharomyces cerevisiae, we cloned the corresponding genes from Oryza sativa, Arabidopsis thaliana, Aspergillus nidulans and Candida albican and expressed them under the control of the galactose-inducible GAL promoter in the fun12Delta strain of Saccharomyces cerevisiae. Expression of Candida albicans eIF5B complemented the slow-growth phenotype of the fun12Delta strain, but that of Aspergillus nidulance did not, despite the fact that its protein was expressed better than that of Candida albicans. The Arabidopsis thaliana protein was also not functional in Saccharomyces. These results reveal that the eIF5B in Candida albicans has a close functional relationship with that of Sacharomyces cerevisiae, as also shown by a phylogenetic analysis based on the amino acid sequences of the eIF5Bs.
Jun
Kyung Ok
KO
Department of Biological Sciences, Sunchon National University, Sunchon 540-742, Korea.
Yang
Eun Ji
EJ
Lee
Byeong Jeong
BJ
Park
Jeong Ro
JR
Lee
Joon H
JH
Choi
Sang Ki
SK
D000595:Amino Acid Sequence; D002176:Candida albicans / Q000166:cytology / Q000378:metabolism*; D039642:Eukaryotic Initiation Factors / Q000737:chemistry / Q000378:metabolism*; D005816:Genetic Complementation Test; D015151:Immunoblotting; D008969:Molecular Sequence Data; D010641:Phenotype; D010802:Phylogeny; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism*; D016415:Sequence Alignment
D039642:Eukaryotic Initiation Factors; C451459:eukaryotic initiation factor-5B