Transcriptional profiling of a genome-reduced strain in Schizosaccharomyces pombe

Gene number of the fission yeast Schizosaccharomyces pombe is the lowest in free-living eukaryotes. We further reduced the gene number to examine a minimal gene set required for growth. The genome-reduced strain, named ASP3894, has four chromosomal deletion regions: 168.4 kb deletion in the left arm of chromosome 1 (ALT), 155.4 kb deletion in the right arm of chromosome 1 (ART), 211.7 kb deletion in the left arm of chromosome 2 (BLT) and 121.6 kb deletion in the right arm of chromosome 2 (BRT). As a result of the 657.3 kb genome reduction, 224 genes of approximately 5100 total genes were reduced. ASP3894 transcriptional profiling was compared with a parent strain, ASP3880, that is a non-genome-reduced strain to examine the influence of genome reduction. Three independent experiments. 3 control ASP3880 samples and 3 genome-reduced strain ASP3894 samples were independently grown in EMM medium and harvested at the logarithmic phase.

裂殖酵母Schizosaccharomyces pombe的基因数目在自由生活的真核生物中最低。本研究进一步缩减其基因数目，以探究维持生长所需的最小基因集。本研究构建的基因组缩减菌株命名为ASP3894，其携带有四处染色体缺失区域：1号染色体左臂存在168.4 kb的缺失（ALT）、1号染色体右臂存在155.4 kb的缺失（ART）、2号染色体左臂存在211.7 kb的缺失（BLT）以及2号染色体右臂存在121.6 kb的缺失（BRT）。本次共计657.3 kb的基因组缩减，使该菌株在总计约5100个基因中删除了224个。为探究基因组缩减的影响，我们将ASP3894的转录谱与亲本菌株ASP3880（非基因组缩减菌株）进行了比对分析。实验设置三次独立重复：分别将3份对照亲本ASP3880样本与3份基因组缩减菌株ASP3894样本在EMM培养基中独立培养，并于对数生长期收获。