RESUMEN
In order to obtain the long-acting FSH preparation, the single strand long-acting analogous gene FSHbeta-CTP-alpha was successfully constructed by the C-terminal peptide(CTP) of carboxyl-terminal region of human chorionic gonadotropin with the goat FSHalpha-subunit and beta-subunit genes, then it was inserted into pPIC9K vector. The recombinant plasmid pPIC9K FSHbeta-CTP-alpha was transformed into Pichia pastoris GS115 by electroporation. The multi-copy inserts His+Mut+ were gained by the screening of phenotype and hyper-resistance to G418. After methanol induction, the supernatant was analysised by SDS-Polyacrylamide Gen Electrophoresis and Western blot. The results show that the transformants of FSHbeta-CTP-alpha could express the objective protein successfully and the molecular weight is about 29 kD. The concentration of supernatant was detected by Radio-immunoassay and the average expression of multi-inserts is 91.849 mIU/mL and the low-inserts is 37.419 mIU/mL. The expression of multi-inserts is higher than the low-inserts significantly. This research lay the foundation for studying the structure of FSH and the production of long-acting FSH preparation.