원문정보
초록
영어
The light-oxygen-voltage (LOV) domain is a member of the PAS (Per-ARNT-Sim) domain superfamily mediating light sensing signals in the cell. Allosteric control of dihydrofolate reductase (DHFR) was explored by creating PAS-DHFR light switch, a chimeric protein that connects a light-sensing signaling domain from A. sativa phototropin (LOV2) with E. coli DHFR. Here, we demonstrate that a light dependent allosteric effect is introduced through linkage of the domain to the coupled catalytic network in DHFR. Light activation of the chimera triggered a characteristic spectral shift to 390 nm due to formation of a covalent thiol-FMN adduct that initiates a conformational change. Among the chimeras, LOV domain insertion into a specific position in the bF-bG loop of the DHFR exhibits light-dependent modulation of the hydride transfer rate. This work clearly proved the presence of unique network(s) in proteins through which a signal is transmitted. The engineering of a light-dependent control represents an initial step for the general development of proteins subject to allosteric regulation.