Microinjected pBR322 stimulates cellular DNA synthesis in Swiss 3T3 cells.
AUTOR(ES)
Hyland, J K
RESUMO
When pBR322 is manually microinjected into the nuclei of quiescent Swiss 3T3 cells it stimulates the incorporation of [3H]thymidine into DNA. The evidence clearly shows that this increased incorporation that is detected by in situ autoradiography in microinjected cells represents cellular DNA synthesis and not DNA repair or plasmid replication. The effect is due to pBR322 and not due to impurities, mechanical perturbances due to the microinjection technique, or aspecific effects. This stimulation is striking in Swiss 3T3 cells. Some NIH 3T3 cells show a slight stimulation, but hamster cells, derived from baby hamster kidney (BHK) cells, are not stimulated when microinjected with pBR322. The preliminary evidence seems to indicate that the integrity of the pBR322 genome is important for the stimulation of cellular DNA synthesis in quiescent Swiss 3T3 cells. These results, although of a preliminary nature, are of interest because they indicate that a prokaryotic genome may alter the cell cycle of mammalian cells. From a practical point of view the stimulatory effect of microinjected pBR322 on cellular DNA synthesis has a more immediate interest, because pBR322 is the vector most commonly used for molecular cloning and 3T3 cells are very frequently used for gene transfer experiments.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=344684Documentos Relacionados
- Cooperativity in nucleosomes assembly on supercoiled pBR322 DNA.
- Conservative integration of bacteriophage Mu DNA into pBR322 plasmid.
- Ozonolysis of supercoiled pBR322 DNA resulting in strand scission to open circular DNA.
- Influence of DNA topology and histone tails in nucleosome organization on pBR322 DNA.
- pBR322 DNA inhibits simian virus 40 gene expression in Xenopus laevis oocytes.
