Transactivation of the early SV40 promoter by avian infectious laryngotracheitis virus in avian hepatoma cells.
An avian hepatoma cell line has been reported to be suitable for the cultivation of avian laryngotracheitis virus (ILTV) (Scholz et al. (1993) J. Virol. Methods, 273-286; Guo et al. (1993) Am. J. Vet. Res., in press). To provide information for the establishment of avian expression systems and for the construction of avian recombinant viruses, five expression plasmids were constructed to test two avian viral and two mammalian viral promotors for their suitability and strength for gene expression in this cell line. Chicken hepatoma cells were transfected with plasmids carrying the bacterial beta-galactosidase (beta-gal) gene as a reporter gene. The beta-gal gene of three plasmid constructs expressed in both E. coli and avian hepatoma cells, while the beta-gal gene of two other constructs expressed only in avian hepatoma cells. The beta-gal gene expressed independently of any viral infection when under the control of the early Rous sarcoma virus (RSV) promoter or the immediate-early cytomegalovirus (CMV) promoter. However, expression of beta-gal gene under the control of the SV40 early promoter/enhancer and the ILTV TK promoter was greatly potentiated when the transfected cells were co-infected with ILTV. This finding provides a system for the enhancement of gene expression in avian cells, especially when ILTV is used as vector.
Scholz
E
E
Department of Veterinary Pathobiology, Purdue University, West Lafayette, IN 47907.
Zhang
C
C
Guo
P
P
D000818:Animals; D001483:Base Sequence; D002645:Chickens; D003001:Cloning, Molecular; D004742:Enhancer Elements, Genetic / Q000235:genetics; D015967:Gene Expression Regulation, Viral / Q000235:genetics*; D005822:Genetic Vectors; D001352:Herpesvirus 1, Gallid / Q000235:genetics*; D008969:Molecular Sequence Data; D010957:Plasmids; D011401:Promoter Regions, Genetic / Q000235:genetics*; D013539:Simian virus 40 / Q000235:genetics; D015533:Transcriptional Activation / Q000235:genetics*; D014162:Transfection; D014407:Tumor Cells, Cultured