LAUSR

Transcriptional regulation is essential for maintaining the natural cell metabolism of microbes and therefore important for metabolic engineering. The development of non-native transcriptional regulation tools in engineered microbes may change the gene expression and metabolic flux, and shall benefit the product titer and yield in bioprocess. CRISPR interference (CRISPRi), as an artificial transcriptor which may regulate any gene at different scales, has rapidly gained popularity for metabolic engineering strains. This article briefly describes the mechanism and development of CRISPRi, including inhibition and activation of two forms of action and several different sources of dCas9 protein. And we summarize the applications of CRISPRi in regulating the metabolic pathway, changing the physiological state of the host, and genomic screening. Finally, we analyze a few limitations of the CRISPRi system and summarize some ways to improve them.