Conformation limited proteolysis in the common neurophysin-copeptin precursor shown by trypsin-sepharose chromatographic proteolysis.
The guinea pig two-domain precursor of MSEL-neurophysin and copeptin has been passed through a trypsin-Sepharose column in order to mimic the enzyme processing by a membrane-bound endopeptidase. Only two cleavages were observed located in the inter-domain sequence (at Arg-94 and Arg-98), in contrast to several additional cleavages found when free neurophysin or copeptin is subjected to soluble trypsin. Because the physiological maturation involves a single cleavage at Arg-94, both local accessibility in the precursor and narrow specificity of the enzyme are implied in the processing.
D000595:Amino Acid Sequence; D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism*; D002846:Chromatography, Affinity; D002847:Chromatography, Agarose; D006020:Glycopeptides / Q000378:metabolism*; D006168:Guinea Pigs; D006868:Hydrolysis; D009481:Neurophysins / Q000378:metabolism*; D010121:Oxytocin; D011498:Protein Precursors / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D014357:Trypsin / Q000378:metabolism*
D006020:Glycopeptides; D009481:Neurophysins; D011498:Protein Precursors; C048197:copeptins; D001127:Arginine Vasopressin; D010121:Oxytocin; D014357:Trypsin