Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Campus UAB, Bellaterra, Barcelona, Spain.
Department of Chemical and Biological Engineering, University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK.
J Exp Bot. 2023 Jul 18;74(13):3833-3850. doi: 10.1093/jxb/erad100.
Microalgae hold enormous potential to provide a safe and sustainable source of high-value compounds, acting as carbon-fixing biofactories that could help to mitigate rapidly progressing climate change. Bioengineering microalgal strains will be key to optimizing and modifying their metabolic outputs, and to render them competitive with established industrial biotechnology hosts, such as bacteria or yeast. To achieve this, precise and tuneable control over transgene expression will be essential, which would require the development and rational design of synthetic promoters as a key strategy. Among green microalgae, Chlamydomonas reinhardtii represents the reference species for bioengineering and synthetic biology; however, the repertoire of functional synthetic promoters for this species, and for microalgae generally, is limited in comparison to other commercial chassis, emphasizing the need to expand the current microalgal gene expression toolbox. Here, we discuss state-of-the-art promoter analyses, and highlight areas of research required to advance synthetic promoter development in C. reinhardtii. In particular, we exemplify high-throughput studies performed in other model systems that could be applicable to microalgae, and propose novel approaches to interrogating algal promoters. We lastly outline the major limitations hindering microalgal promoter development, while providing novel suggestions and perspectives for how to overcome them.
微藻具有提供安全可持续的高价值化合物的巨大潜力，可作为固碳生物工厂，有助于缓解快速发展的气候变化。生物工程微藻菌株将是优化和修饰其代谢产物的关键，使其具有竞争力，以取代现有的工业生物技术宿主，如细菌或酵母。为了实现这一目标，需要对转基因表达进行精确和可调的控制，这将需要开发和合理设计合成启动子作为关键策略。在绿色微藻中，莱茵衣藻是生物工程和合成生物学的参考物种；然而，与其他商业底盘相比，该物种和微藻的功能合成启动子库有限，这强调了需要扩展当前的微藻基因表达工具包。在这里，我们讨论了最先进的启动子分析，并强调了推进莱茵衣藻合成启动子开发所需的研究领域。特别是，我们举例说明了在其他模型系统中进行的高通量研究，这些研究可能适用于微藻，并提出了新的方法来研究藻类启动子。最后，我们概述了阻碍微藻启动子开发的主要限制，并提供了克服这些限制的新建议和观点。
