Generation of conditionally controlled transgenic mice expressing hepatitis C virus NS3/4A protease

Objective To establish conditionally regulated transgenic mice expressing hepatitis C virus(HCV) NS3 4A serine protease.Methods A recombinant plasmid PBI-Ⅲ/LoxP-Luc-PolyA-LoxP-NS3/4A was constructed by molecular cloning and transgenic mice were generated by microinjection of fertilized ovum with the larger linearized fragment obained by enzyme digesting the recombinant vector.Founder mouse and positive offsprings detected by polymerase chain reaction(PCR) were interbred with C57BL/6 mouse to establish a defined genetic background.Part of the second generations were interbred with another transgenic mouse Lap which have been stable and systematically constructed.The interbred dual transgenic offsprings previously induced with doxycycline(Dox) were detected by in vivo bioluminescent imaging(BLI).The imaging positive dual transgenics were reserved and their NS3/4A transgenic parents were interbred with C57BL/6 instead.Results Restriction analysis and sequence analysis showed that the recombinant plasmid PBI-Ⅲ/LoxP-Luc-PolyA-LoxP-NS3/4A was successfully constructed.6 founder transgenic mouse were obtained and 3 of them have been spread to fourth generation.Transgenic mouse stably expressing the exogenous reporter gene luciferase(Luc) were selected by BLI.Conclusion Transgenic mouse conditionally expressing HCV NS3/4A serine protease were successfully generated.