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CRISPR‐Cas9 technology has been successfully applied inYarrowia lipolyticafor targeted genomic editing including gene disruption and integration; however, disruptions by existing methods typically result from small frameshift mutations caused by indels within the coding region, which usually resulted in unnatural protein. In this study, a dual cleavage strategy directed by paired sgRNAs is developed for gene knockout. This method allows fast and robust gene excision, demonstrated on six genes of interest. The targeted regions for excision vary in length from 0.3 kb up to 3.5 kb and contain both non‐coding and coding regions. The majority of the gene excisions are repaired by perfect nonhomologous end‐joining without indel. Based on this dual cleavage system, two targeted markerless integration methods are developed by providing repair templates. While both strategies are effective, homology mediated end joining (HMEJ) based method are twice as efficient as homology recombination (HR) based method. In both cases, dual cleavage leads to similar or improved gene integration efficiencies compared to gene excision without integration. This dual cleavage strategy will be useful for not only generating more predictable and robust gene knockout, but also for efficient targeted markerless integration, and simultaneous knockout and integration inY. lipolytica.
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Advances and opportunities in gene editing and gene regulation technology for Yarrowia lipolytica
Abstract Yarrowia lipolytica has emerged as a biomanufacturing platform for a variety of industrial applications. It has been demonstrated to be a robust cell factory for the production of renewable chemicals and enzymes for fuel, feed, oleochemical, nutraceutical and pharmaceutical applications. Metabolic engineering of this non-conventional yeast started through conventional molecular genetic engineering tools; however, recent advances in gene/genome editing systems, such as CRISPR–Cas9, transposons, and TALENs, has greatly expanded the applications of synthetic biology, metabolic engineering and functional genomics of Y. lipolytica . In this review we summarize the work to develop these tools and their demonstrated uses in engineering Y. lipolytica , discuss important subtleties and challenges to using these tools, and give our perspective on important gaps in gene/genome editing tools in Y. lipolytica .
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- PAR ID:
- 10222171
- Date Published:
- Journal Name:
- Microbial Cell Factories
- Volume:
- 18
- Issue:
- 1
- ISSN:
- 1475-2859
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1186/s12934-019-1259-x
