title: De novo origination of a new protein-coding gene in Saccharomyces cerevisiae.
abstract: Origination of new genes is an important mechanism generating genetic novelties during the evolution of an organism. Processes of creating new genes using preexisting genes as the raw materials are well characterized, such as exon shuffling, gene duplication, retroposition, gene fusion, and fission. However, the process of how a new gene is de novo created from noncoding sequence is largely unknown. On the basis of genome comparison among yeast species, we have identified a new de novo protein-coding gene, BSC4 in Saccharomyces cerevisiae. The BSC4 gene has an open reading frame (ORF) encoding a 132-amino-acid-long peptide, while there is no homologous ORF in all the sequenced genomes of other fungal species, including its closely related species such as S. paradoxus and S. mikatae. The functional protein-coding feature of the BSC4 gene in S. cerevisiae is supported by population genetics, expression, proteomics, and synthetic lethal data. The evidence suggests that BSC4 may be involved in the DNA repair pathway during the stationary phase of S. cerevisiae and contribute to the robustness of S. cerevisiae, when shifted to a nutrient-poor environment. Because the corresponding noncoding sequences in S. paradoxus, S. mikatae, and S. bayanus also transcribe, we propose that a new de novo protein-coding gene may have evolved from a previously expressed noncoding sequence.
authors.affiliation: CAS-Max Planck Junior Research Group on Evolutionary Genomics, State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China .
authors.forename: Jing
authors.initials: J
authors.lastname: Cai
authors.forename: Ruoping
authors.initials: R
authors.lastname: Zhao
authors.forename: Huifeng
authors.initials: H
authors.lastname: Jiang
authors.forename: Wen
authors.initials: W
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D016000:Cluster Analysis; D019295:Computational Biology; D017931:DNA Primers / Q000235:genetics; D004260:DNA Repair / Q000235:genetics*; D019143:Evolution, Molecular; D005800:Genes, Fungal / Q000235:genetics*; D005828:Genetics, Population; D008969:Molecular Sequence Data; D010802:Phylogeny; D040901:Proteomics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D026801:Synteny / Q000235:genetics
chemical_list: D017931:DNA Primers; D029701:Saccharomyces cerevisiae Proteins