SYNTHETIC DNA FRAGMENT FOR CELL EXPRESSION AND METHOD FOR PREPARATION

PROBLEM TO BE SOLVED: To eliminate problems that several days are required to obtain the objective subclone and a longer time is required to prepare a large amount of a plasmid DNA necessary for transfection though subcloning of the objective gene coding part from a cDNA clone into an expression vector is required in an expression experiment in a culture cell. SOLUTION: A method for preparing a DNA fragment comprising a promoter, the objective gene, an expression marker gene, a terminator sequence and a polyadenylation signal sequence which are a sequence necessary for expression in a cell by using a polymerase chain reaction (PCR) method in place of preparation of the plasmid DNA for expression in a shorter time is developed. Furthermore, cyclization of the DNA fragment for expression is provided as a means effective in avoiding an attack of a DNA-degrading enzyme on an extraneous DNA caused after transfer into the cell in the method. COPYRIGHT: (C)2004,JPO