Efficient DNA transfection in neuronal and astrocytic cell lines

We have studied different parameters for efficient DNA transfection in vari ous cell types and with different size of the promoter. Here we report that the optimum condition for DNA transfection by electroporation is 350 V/960 muF for PC12, 450V/960 muF C6 cells, and 250 V/500 muF for COS-1 cells. Fo r the human neuroblastoma (SK-N-SH) cells the optimum condition for DNA tra nsfection is by the calcium phosphate method. In promoter mapping studies, a serial deletion approach is commonly used. To optimize transfection we ha ve selected three DNA constructs that varied in size from 4.5 to 12.4 kilob ases (kb). We measured the promoter activity of these constructs under cond itions of 'equal amount', 'equimolar', and 'equimolar plus carrier DNA to m ake it equal amount'. We recommend that for comparative purpose, transfecti on should be carried out under 'equimolar condition' without a need to adju st the total amount of DNA by carrier DNA. Taken together, our results sugg est that efficient methods for DNA transfection are important to study gene regulation by devising better ways to deliver DNA into the mammalian cells .