Establishment of novel screening and targeting novel coronavirus protease 3CLpro activity system

The invention relates to establishment of a novel screening and targeting novel coronavirus protease 3CLpro activity system, and belongs to the technical field of molecular biology. According to the invention, a eukaryotic cell expression vector VR1012 is used for expressing partial ORF1ab sequences with different tags at the N end and the C end as detection plasmids. A detection plasmid and a 3CLpro expression vector are co-transfected in a cell, the detection plasmid is used for expressing a tag antibody at the end 2 of a sequence, and the activity of the 3CLpro proteolytic enzyme is reflected by detecting the ratio of a fragment at the end 2 after 3CLpro is cut to a full-length uncut fragment. The detection system established by the invention is high in detection sensitivity, and can be used for detecting two 3CLpro shear sites Q < S > and Q < A >. Compared with an FRET system which is put into use, the FRET system has the advantages that the space structure of a substrate peptide fragment when the 3CLpro