Adenovirus E1A 12S protein induces DNA synthesis and proliferation in primary epithelial cells in both the presence and absence of serum.
AUTOR(ES)
Quinlan, M P
RESUMO
Infection of primary baby rat kidney (BRK) cells with an adenovirus that carries an E1A 12S cDNA in place of the normal E1A region (adenovirus 5 [Ad5] 12S) resulted in the induction of cellular DNA synthesis and proliferation of the epithelial cells in the population, even in the absence of serum. Increased cellular DNA synthesis was first detectable by 12 h after infection and was maintained at a 10- to 20-fold higher level than in mock-infected cells. By 5 days after infection there was a 10-fold-greater number of 12S virus-infected BRK cells. These infected BRK cells retained many of their normal epithelial cell characteristics and were not transformed. The expression of the E1A 12S protein(s) occurred early after infection. There was no induction of adenoviral gene expression or viral DNA replication in these cells. The early effects of a fully transforming gene product(s) were also examined. The Ad5-simian virus 40 hybrid virus, Ad5.SVR4, in which the early region of simian virus 40 has replaced the E1 region of Ad5, was used to infect BRK cells. The kinetics of expression of the T antigens were similar to those of the 12S polypeptides. Infection with Ad5.SV4 also resulted in the induction of cellular DNA synthesis and cell proliferation at levels similar to those observed with the 12S virus. However, infection with Ad5.SVR4 resulted in cells that had lost some of their epithelial cell characteristics and were fully transformed. Thus, although the early cellular events induced by the two genes were similar, they did not yield the same final cellular phenotype.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=254006Documentos Relacionados
- Growth factor induction by the adenovirus type 5 E1A 12S protein is required for immortalization of primary epithelial cells.
- Adenovirus 12S E1A gene represses differentiation of F9 teratocarcinoma cells.
- Selective induction of human heat shock gene transcription by the adenovirus E1A gene products, including the 12S E1A product.
- A retrovirus expressing the 12S adenoviral E1A gene product can immortalize epithelial cells from a broad range of rat tissues.
- The adenovirus E1A 12S product displays functional redundancy in activating the human proliferating cell nuclear antigen promoter.