Gene responses to oxygen availability in Kluyveromyces lactis: an insight on the evolution of the oxygen-responding system in yeast.
The whole-genome duplication (WGD) may provide a basis for the emergence of the very characteristic life style of Saccharomyces cerevisiae-its fermentation-oriented physiology and its capacity of growing in anaerobiosis. Indeed, we found an over-representation of oxygen-responding genes in the ohnologs of S. cerevisiae. Many of these duplicated genes are present as aerobic/hypoxic(anaerobic) pairs and form a specialized system responding to changing oxygen availability. HYP2/ANB1 and COX5A/COX5B are such gene pairs, and their unique orthologs in the 'non-WGD' Kluyveromyces lactis genome behaved like the aerobic versions of S. cerevisiae. ROX1 encodes a major oxygen-responding regulator in S. cerevisiae. The synteny, structural features and molecular function of putative KlROX1 were shown to be different from that of ROX1. The transition from the K. lactis-type ROX1 to the S. cerevisiae-type ROX1 could link up with the development of anaerobes in the yeast evolution. Bioinformatics and stochastic analyses of the Rox1p-binding site (YYYATTGTTCTC) in the upstream sequences of the S. cerevisiae Rox1p-mediated genes and of the K. lactis orthologs also indicated that K. lactis lacks the specific gene system responding to oxygen limiting environment, which is present in the 'post-WGD' genome of S. cerevisiae. These data suggested that the oxygen-responding system was born for the specialized physiology of S. cerevisiae.
Université Paris Sud-11, CNRS UMR 8621, Institut de Génétique et Microbiologie, Orsay, France.
Zi-An
ZA
Fang
Guang-Hui
GH
Wang
Ai-Lian
AL
Chen
You-Fang
YF
Li
Jian-Ping
JP
Liu
Yu-Yang
YY
Li
Monique
M
Bolotin-Fukuhara
Wei-Guo
WG
Bao
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D019295:Computational Biology / Q000379:methods; D015966:Gene Expression Regulation, Fungal; D016681:Genome, Fungal; D023281:Genomics; D007716:Kluyveromyces / Q000235:genetics* / Q000378:metabolism*; D008954:Models, Biological; D008969:Molecular Sequence Data; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013269:Stochastic Processes
D010100:Oxygen