The Chemical Synthesis And Functional Study Of Truncated Peptide COX_52-69

A truncated peptide can inhibit insulin secretion was obtained from pig intestine,By amino acid sequence analysis,we found it was a small molecule peptide contains of 18 amino acids.and we also found it overlaps cytochrome oxidase?52 to 69amino acids completely through the amino acid sequence alignment,so the truncated peptide was named after COX_52-69.however,we found cytochrome oxidase?couldn't inhibit the secretion of insulin through literature retrieval.This implies a long peptide or mother peptide may be digested into a truncated peptide which has a new function.The function of daughter peptide may be different from mother peptide.This may be a pattern that peptide plays various key roles in all aspects of biology.In order to explore the effect of COX_52-69,We used Fmoc solid phase synthesis method and got high purity of COX_52-69peptide.By using SD rats in vivo and in vitro experiment,and rat islet cell line RIN-m5f in cell experiment.we also find that synthetic COX_52-69can inhibit the secretion of insulin.In order to explore the related molecular mechanism of COX_52-69peptide inhibit insulin secretion.We tried if COX_52-69impact on the intracellular molecular concentration of c AMP at a cellular level.Regrettably the hyperthesis is not confirmed.Although it was negative result,at least,it implied that the role of synthetic COX_52-69peptide on inhibitting insulin secretion.may not be by influencing the c AMP..In brief,the study suggests a polypeptide may be digested into a variety of truncated peptide by enzyme.The truncated peptide may have theirself functions like the role of COX_52-69totally different from the parent peptide.It also offers a new thought for understanding some physiological functiona and the development of new drugs.