Light-regulated tetracycline binding to the Tet repressor = 빛을 이용한 DNA 결합 조절 기술

Abstract

Elucidation of the signal-transmission pathways between distant sites within proteins is of great importance in medical and bioengineering sciences. The use of optical methods to redesign protein functions is emerging as a general approach for the control of biological systems with high spatiotemporal precision. Here we report the detailed thermodynamic and kinetic characterization of novel chimeric light-regulated Tet repressor (TetR) switches in which light modulates the TetR function. Light absorbed by flavin mononucleotide (FMN) generates a signal that is transmitted to As-LOV and YtvA-LOV fused TetR proteins (LOV=light-oxygen-voltage), in which it alters the binding to tetracycline, the TetR ligand. The engineering of light-sensing protein modules with TetR is a valuable tool that deepens our understanding of the mechanism of signal transmission within proteins. In addition, the light-regulated changes of drug binding that we describe here suggest that engineered light-sensitive proteins may be used for the development of novel therapeutic strategies. Tet-a-tet: Light absorbed by flavin mononucleotide (FMN) generates a signal that is transmitted to the light-oxygen-voltage (LOV) domain fused Tet repressor proteins (see figure), in which it alters the binding to tetracycline, thereby controlling the tetO DNA binding affinity.