Abstract:The transient transfection of β2AR gene to mammalian cells HEK293 was investigated, and then the expressed product was purified and identified. The constructed recombinant plasmid was transiently transfected into HEK293 cells. Then the expressed product was treated by crude membrane preparation and purification through Ni-NTA-affinity chromatography. Subsequently, the content and activity of the recombinant protein was identified. The results showed that the HEK293 cells transfected with pTriEx-1.1 Hygro-β2AR1-418 exhibited higher expression effect, and the optimal expression was 72 h after transfection. The results of SDS-PAGE and Western blot indicated that a specific band was seen at 47 ku, the optimal imidazole concentration was 250 mmol/L, and the purity of the protein was more than 80%. The activitiy assay revealed that the recombinant receptor could bind all 3 HRP-β-agonists, and the OD values obtained from the ELISA for detection HRP-CBL, HRP-RAC and HRP-SAL were 0.97, 0.91 and 0.94，respectively. The yield of the receptor protein was 4.42% of crude membrane. In brief, a certain amount of β2AR protein with comparatively ideal purity and activity was obtained, laying a foundation for the development and application of β2AR in multi-residues determination of β-agonists.
