Author:
An Yan,Talwar Chandana S.,Park Kwang-Hyun,Ahn Woo-Chan,Lee Su-Jin,Go Seong-Ryeong,Cho Jin Hwa,Kim Do Yon,Kim Yong-Sam,Cho Sayeon,Kim Jeong-Hoon,Kim Tae-Jip,Woo Eui-Jeon
Abstract
AbstractThe CRISPR–Cas9 system is a widely used gene-editing tool, offering unprecedented opportunities for treating various diseases. Controlling Cas9/dCas9 activity at specific location and time to avoid undesirable effects is very important. Here, we report a conditionally active CRISPR–Cas9 system that regulates target gene expression upon sensing cellular environmental change. We conjugated the oxygen-sensing transcription activation domain (TAD) of hypoxia-inducing factor (HIF-1α) with the Cas9/dCas9 protein. The Cas9-TAD conjugate significantly increased endogenous target gene cleavage under hypoxic conditions compared with that under normoxic conditions, whereas the dCas9-TAD conjugate upregulated endogenous gene transcription. Furthermore, the conjugate system effectively downregulated the expression of SNAIL, an essential gene in cancer metastasis, and upregulated the expression of the tumour-related genes HNF4 and NEUROD1 under hypoxic conditions. Since hypoxia is closely associated with cancer, the hypoxia-dependent Cas9/dCas9 system is a novel addition to the molecular tool kit that functions in response to cellular signals and has potential application for gene therapeutics.
Funder
National Research Foundation of Korea
KRIBB Research Initiative
Publisher
Springer Science and Business Media LLC