Methods: The transient expression system of COS7 was constructed by using pcDNA3.1-sEGFR501 expression vector and the process of Calcium-phosphate co-precipitation transfection was optimized with Enhanced Green Fluorescent Protein (EGFP) as a reporter.

• 方法：以增强型绿色荧光蛋白(EGFP)基因为报告基因，优化磷酸钙共沉淀转染COS7的实验参数； 以pcDNA3.；1-sEGFR501和COS7组建瞬时表达系统。