Long-acting recombinant neuritin with increased stability

Abstract Objective: To obtain the long-acting protein neuritin we fused the carboxyl-terminal peptide (CTP) to the C-terminal of neuritin and expressed it in Chinese hamster ovarian (CHO) cells. Methods：The plasmid was constructed by fusion PCR. Affinity chromatography is used for protein purification. Thermal stability and serum stability were used to evaluate protein stability. Results: The molecular weight of the neuritin-CTP was determined to be approximately 20 kDa. Subsequent functional analysis showed that the purified neuritin-CTP promoted neurite outgrowth in PC12 cells at a rate equivalent to that observed with neuritin. The stability experiments showed that the degradation rate of neuritin was 100% after incubation at 37°C for 72 h, whereas only approximately 20% of the neuritin-CTP was degraded under the same conditions. Similarly, the serum stability analysis results showed that neuritin degraded by approximately 90% and neuritin-CTP degraded by approximately 30% after incubation at 37°C for 72 h. Conclusions: Fusion with CTP can effectively increase the stability of neuritin without affecting its secretion and activity. These results provide a basis for the construction of long-acting neuritin proteins.