The genome sequence of Schizosaccharomyces pombe

Abstract

We have sequenced and annotated the genome of ®ssion yeast (Schizosaccharomyces pombe), which contains the smallest number of protein-coding genes yet recorded for a eukaryote: 4,824. The centromeres are between 35 and 110 kilobases (kb) and contain related repeats including a highly conserved 1.8-kb element. Regions upstream of genes are longer than in budding yeast (Saccharomyces cerevisiae), possibly re¯ecting more-extended control regions. Some 43% of the genes contain introns, of which there are 4,730. Fifty genes have signi®cant similarity with human disease genes; half of these are cancer related. We identify highly conserved genes important for eukaryotic cell organization including those required for the cytoskeleton, compartmentation, cell-cycle control, proteolysis, protein phosphorylation and RNA splicing. These genes may have originated with the appearance of eukaryotic life. Few similarly conserved genes that are important for multicellular organization were identi®ed, suggesting that the transition from prokaryotes to eukaryotes required more new genes than did the transition from unicellular to multicellular organization.We report here the completion of the fully annotated genome sequence of the simple eukaryote Schizosaccharomyces pombe, a ®ssion yeast. It becomes the sixth eukaryotic genome to be sequenced, following Saccharomyces cerevisiae 1 , Caenorhabditis elegans 2 , Drosophila melanogaster 3 , Arabidopsis thaliana 4 and Homo sapiens 5,6 . The entire sequence of the unique regions of the three chromosomes is complete, with gaps in the centromeric regions of about 40 kb, and about 260 kb in the telomeric regions. The completion of this sequence, the availability of sophisticated research methodologies, and the expanding community working on S. pombe, will accelerate the use of S. pombe for functional and comparative studies of eukaryotic cell processes.

Increased TCA cycle activity and reduced oxygen consumption during cytochrome P450‐dependent biotransformation in fission yeast

“…erg11 ; a predicted sterol C-14α demethylase) and CYP61 (syn. erg5 ; a predicted sterol C-22 desaturase), respectively (Wood et al, 2002). Since it is known that the microsomal P450 system of yeast is a major source of reactive oxygen species (ROS; Rosenfeld et al, 2002), the model takes both substrate hydroxylation and ROS production into account (Figure 3).…”

Evolutionary patterns of non-coding RNAs

“…Typical Eukaryotes contain tandemly repeated arrays of rRNAs genes each of which contains three of the four ribosomal RNA components separated by two "internally transcribed spacers" (18S/ITS1/5.8S/ITS2/28S) [155]. In most species the fourth rRNA gene, 5S rRNA, is also contained in this array, while it sometimes is dispersed throughout the genome (as in Schizosaccharomyces pombe, [441]), organized in its own tandem arrays (as in soybeans [128]), or both (as in humans [252]). For each of these genes, however, the rDNA sequences that are represented in fully processed rRNA are essentially identical in most organisms, i.e., rRNA genes are subject to concerted evolution [155,361,121].…”

A ‘marker switch’ approach for targeted mutagenesis of genes in Schizosaccharomyces pombe

“…The site is either 3 or 5 , but is one which one anticipates will not adversely affect the transcription or termination of the message of goi1 + , or its neighbouring genes. A check of the genome database (Wood et al, 2002) occurred to isolate any single integrants at the goi1 locus that may have the required phenotype. Once a mutation with the desired phenotype has been identified, the ura4 + marker can be removed by transformation of a fragment spanning the insertion site and selection on 5-fluoro-orotic acid (FOA) to identify strains in which recombination has 'flipped out' the ura4 + gene.…”