Influence of the helper virus on expression of beta-galactosidase from a defective HSV-1 vector, pHSVlac.
Defective herpes simplex virus type 1 (HSV-1) vectors can deliver genes into both mitotic and postmitotic cells, including neurons and these vectors, therefore, have great potential use. pHSVlac, the prototype HSV-1 vector, expresses the E. coli Lac Z gene from the HSV-1 immediate early 4/5 promoter. pHSVlac can stably express beta-galactosidase in a range of mammalian cell lines and in neurons from throughout the nervous system, both in culture and in the adult rat brain. Thus, HSV-1 vectors may be useful for studying HSV-1 latency, neuronal physiology, and performing gene therapy for neurological conditions. A virus stock of pHSVlac consists of identical HSV-1 particles containing either pHSVlac DNA or the HSV-1 helper virus DNA. Thus, a cell can be infected with the pHSVlac virus, the helper virus, or both; consequently, it is important to determine if the helper virus influences the behavior of pHSVlac. The effect of the helper virus on expression of beta-galactosidase from pHSVlac was investigated: it was demonstrated first, that pHSVlac can be efficiently packaged into HSV-1 virus particles using each of five HSV-1 temperature sensitive (ts) mutants as helper virus. Second, pHSVlac grown with each of the five HSV-1 ts mutants expressed high levels of beta-galactosidase. Third, pHSVlac grown with HSV-1 strain 17 ts K as helper virus expresses the same amount of beta-galactosidase in the absence or presence of ts K. Thus, pHSVlac can efficiently express a gene independent of the HSV-1 helper virus.
Geller
A I
AI
Laboratory of Neurogenetics, Department of Neurology, Mass. General Hospital, Boston.
D000310:Adrenal Gland Neoplasms; D000818:Animals; D004279:DNA, Viral / Q000032:analysis; D015967:Gene Expression Regulation, Viral; D005822:Genetic Vectors; D000882:Haplorhini; D006378:Helper Viruses / Q000235:genetics*; D009154:Mutation; D010673:Pheochromocytoma; D051381:Rats; D018139:Simplexvirus / Q000201:enzymology / Q000235:genetics*; D014407:Tumor Cells, Cultured; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics*
D004279:DNA, Viral; D001616:beta-Galactosidase