| 摘要 |
PROBLEM TO BE SOLVED: To provide an expression vector capable of reproducibly and efficiently screening for a transformant, particularly a productive cell line of an animal cultured cell, which highly expresses an objective protein, particularly an objective protein having no appropriate assay system. SOLUTION: This expression vector is a vector containing (a) an expression unit containing the first selected marker, (b) a cloning site for inserting a gene encoding the objective protein, and (c) an expression unit containing the second selected marker different from the first selected marker, wherein the cloning site is inserted closely between the two expression units. |
