Fig. 5.
Cloning of the TGEV cDNA in BACs and expression of GFP: A. Plasmid pBAC-TGEVFL (bottom plasmid) was generated using two plasmids, one containing all the virus genome (top plasmid) except a sequence of about 5 kb present between two Cla I sites cloned in a second plasmid (middle plasmid). CMV, cytomegalovirus immediate-early promoter; Poly(A), tail of 24 A residues; HDV, hepatitis delta virus ribozyme; BGH, bovine growth hormone termination and polyadenylation sequences; SC11, S gene of PUR-C11 strain. B. Expression of GFP using an infectious TGEV cDNA clone. Genes 3a and 3b were deleted in the TGEV infectious cDNA, cloned in BAC, leading to a replication competent cDNA (pBAC-TGEV-Δ3ab-GFP). GFP gene (0.72 kb) was inserted within the position of the deleted genes after the TRS of gene 3a. GFP, green fluorescent protein. SC11, S gene of PUR-C11 TGEV strain. An, poly A. HDV, hepatitis delta-virus ribozyme. BGH, bovine growth hormone termination and polyadenylation signals.