A single circular chromosome yeast.
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ABSTRACT:
SUBMITTER: Shao Y
PROVIDER: S-EPMC6318310 | biostudies-literature | 2019 Jan
REPOSITORIES: biostudies-literature
Publications
A single circular chromosome yeast.
Shao Yangyang Y Lu Ning N Cai Chen C Zhou Fan F Wang Shanshan S Zhao Zhihu Z Zhao Guoping G Zhou Jin-Qiu JQ Xue Xiaoli X Qin Zhongjun Z
Cell research 20181217 1
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Project description:BackgroundRedundancy is a common feature of genomes, presumably to ensure robust growth under different and changing conditions. Genome compaction, removing sequences nonessential for given conditions, provides a novel way to understand the core principles of life. The synthetic chromosome rearrangement and modification by loxP-mediated evolution (SCRaMbLE) system is a unique feature implanted in the synthetic yeast genome (Sc2.0), which is proposed as an effective tool for genome minimization. As the Sc2.0 project is nearing its completion, we have begun to explore the application of the SCRaMbLE system in genome compaction.ResultsWe develop a method termed SCRaMbLE-based genome compaction (SGC) and demonstrate that a synthetic chromosome arm (synXIIL) can be efficiently reduced. The pre-introduced episomal essential gene array significantly enhances the compacting ability of SGC, not only by enabling the deletion of nonessential genes located in essential gene containing loxPsym units but also by allowing more chromosomal sequences to be removed in a single SGC process. Further compaction is achieved through iterative SGC, revealing that at least 39 out of 65 nonessential genes in synXIIL can be removed collectively without affecting cell viability at 30 °C in rich medium. Approximately 40% of the synthetic sequence, encoding 28 genes, is found to be dispensable for cell growth at 30 °C in rich medium and several genes whose functions are needed under specified conditions are identified.ConclusionsWe develop iterative SGC with the aid of eArray as a generic yet effective tool to compact the synthetic yeast genome.
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