Fig. 1

Design and expression of plasmid expressing ns1 and ns2A gene. a The pRc/CMV.NS1-2A.HA plasmid contain an N-terminal signal sequence consisting of the last 23 residue of MVEV E protein and encodes an HA tag at the C terminus of NS2A. Shown below is the amino acid sequence of the MVEV octapeptide (P1 – P8) with the N-terminal residue of NS2A (P1’). b Cleavage at the NS1-2A junction of wt and octapeptide mutant construct, P3-Phe. Lysates of radiolabelled COS-7 cells transfected with wt or mutant construct, P3- Phe, or mock-transfected, were immunoprecipitated with an anti-HA-tag mAb. The recovered proteins were treated with endoH (+) or left untreated (−), and analysed by SDS- PAGE (12.5 % acrylamide). Position and size (in kilodaltons) of marker proteins are indicated on left. Bands corresponding to cleaved NS2A, and glycosylated and deglycosylated NS1-2A precursors are labelled. The data are representative of three independent experiments