2019 Volume 7 Issue 1 Pages 7-15
Interferon-tau (IFN-τ:195 aa) is a unique protein secreted only from ruminant and plays a very important role of pregnancy recognition. However, the source of IFN-τ is recombinant IFN-τ using E.coli expression system and it is very difficult to obtain. Therefore basic research and application research for improving pregnancy is highly limited. Besides, use of recombinant IFN-τ for field application is strictly regulated by biosafety and public consensus. Therefore, the purpose of this research is to discover the active site of IFN-τ by using of synthetic peptides as a substitute for recombinant IFN-τ. Eleven peptides (long chain: 27-28 aa, short chain: 7-17 aa) were chemically synthesized from amino acid sequence of IFN-τ. To confirm the agonistic activity of the synthetic peptides, single or mixed peptides were added to cultured bovine endometrium stromal cells to detect gene expression of interferonstimulated genes (ISGs). Recombinant IFN-τ was also added as a positive control. Next experiment was performed to confirm the antagonistic activity of the synthetic peptides. Single or mixed peptides was added to stromal cells with recombinant IFN-τ followed by detecting of ISGs expression. IFN-τ significantly stimulated ISGs expression, whereas all peptides did not stimulate. Besides, addition of single or mixed peptides with IFN-τ showed no inhibitory effect. Overall results suggest that synthetic peptides would not have sufficient agonistic and antagonistic ability or lost the binding ability to IFN receptor by the possible structural change or no activity site having.