title: Yeast KEX2 endopeptidase correctly cleaves a neuroendocrine prohormone in mammalian cells.
abstract: Mammalian cell lines (BSC-40, NG108-15, and GH4C1) that cannot process the murine neuroendocrine peptide precursor prepro-opiomelanocortin (mPOMC) when its synthesis is directed by a vaccinia virus vector were coinfected with a second recombinant vaccinia virus carrying the yeast KEX2 gene, which encodes an endopeptidase that cleaves at pairs of basic amino acid residues. mPOMC was cleaved intracellularly to a set of product peptides normally found in vivo, including mature gamma-lipotropin and beta-endorphin1-31. In GH4C1 cells (a rat pituitary line), product peptides were incorporated into stored secretory granules. These results suggest that the inability of any particular cell line to process a prohormone precursor is due to the absence of a suitable endogenous processing enzyme.
authors.affiliation: Vollum Institute for Advanced Biomedical Research, Oregon Health Sciences University, Portland 97201.
authors.forename: G
authors.initials: G
authors.lastname: Thomas
authors.forename: B A
authors.initials: BA
authors.lastname: Thorne
authors.forename: L
authors.initials: L
authors.lastname: Thomas
authors.forename: R G
authors.initials: RG
authors.lastname: Allen
authors.forename: D E
authors.initials: DE
authors.lastname: Hruby
authors.forename: R
authors.initials: R
authors.lastname: Fuller
authors.forename: J
authors.initials: J
authors.lastname: Thorner
mesh_terms: D002460:Cell Line; D003001:Cloning, Molecular; D004274:DNA, Recombinant; D010450:Endopeptidases / Q000378:metabolism*; D066298:In Vitro Techniques; D011333:Pro-Opiomelanocortin / Q000378:metabolism*; D011498:Protein Precursors / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D012441:Saccharomyces cerevisiae / Q000201:enzymology
chemical_list: D004274:DNA, Recombinant; D011498:Protein Precursors; D011333:Pro-Opiomelanocortin; D010450:Endopeptidases