Synthetic chromosome arms function in yeast and generate phenotypic diversity by design. Nature

High Throughput Biology Center, Johns Hopkins University School of Medicine, 733 North Broadway, Baltimore, Maryland 21205, USA.
Nature (Impact Factor: 41.46). 09/2011; 477(7365):471-6. DOI: 10.1038/nature10403
Source: PubMed


Recent advances in DNA synthesis technology have enabled the construction of novel genetic pathways and genomic elements, furthering our understanding of system-level phenomena. The ability to synthesize large segments of DNA allows the engineering of pathways and genomes according to arbitrary sets of design principles. Here we describe a synthetic yeast genome project, Sc2.0, and the first partially synthetic eukaryotic chromosomes, Saccharomyces cerevisiae chromosome synIXR, and semi-synVIL. We defined three design principles for a synthetic genome as follows: first, it should result in a (near) wild-type phenotype and fitness; second, it should lack destabilizing elements such as tRNA genes or transposons; and third, it should have genetic flexibility to facilitate future studies. The synthetic genome features several systemic modifications complying with the design principles, including an inducible evolution system, SCRaMbLE (synthetic chromosome rearrangement and modification by loxP-mediated evolution). We show the utility of SCRaMbLE as a novel method of combinatorial mutagenesis, capable of generating complex genotypes and a broad variety of phenotypes. When complete, the fully synthetic genome will allow massive restructuring of the yeast genome, and may open the door to a new type of combinatorial genetics based entirely on variations in gene content and copy number.

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    • "So far synthetic biology is contributing the most for synthetic DNA production and modifications of protein structures (Annaluru et al. 2014; Dymond et al. 2011; Dantas et al. 2006). Additionally, toggle switches, cell oscillators and biosensors for instant feedback of transcript, protein or metabolite "
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    • "Although it is often stated that the availability of biobricks will be the major bottleneck in advances in synthetic biology, a more fundamental challenge will likely be to completely map and design a functional cell and optimize it to the level of robust performance required for commercial operation (Stephanopoulos, 2012). That is why, so far, the majority of studies applying synthetic biology are still leaning more toward basic biology rather than applied research (Serrano, 2007; Dymond et al., 2011; Voordeckers et al., 2013). "
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    • "Synthetic genomic approaches focus on understanding function and regulation of multi-gene pathways, function of chromosome architecture, and strategies for multi-locus engineering. Several recent examples of synthetic genomic approaches include the creation of a bacterial cell from a chemically-synthesized genome [1], the cloning and manipulation of entire bacterial chromosomes in Bacillus subtilis[2,3], and efforts to synthesize and shuffle yeast chromosomes [4-6]. "
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