title: Characterization of Molecules Involved in Protein Translocation Using a Specific Antibody
creator: Meyer, David I.
creator: Louvard, Daniel
creator: Dobberstein, Bernhard
subject: ddc-570
subject: 570 Life sciences
description: The vectorial translocation of nascent proteins through the membrane of the rough endoplasmic reticulum has been shown to require a specific membrane-bound protein whose  cytoplasmic domain can be proteolytically cleaved and isolated as an active peptide of mol wt 60,000 (Meyer and Dobberstein, 1980, J. Cell Biol. 87:503-508).  Rabbit antibodies raised against this peptide were used to further characterize the membrane-bound molecule. Immunoprecipitation of solubilized, radiolabeled rough microsomal proteins yielded a single polypeptide of mol wt 72,000, representing the membrane-bound protein from which the 60,000-mol wt peptide was proteolytically derived . The antibody could also be used to remove exclusively the 60,000-mol wt peptide, and thus the translocation activity, from elastase digests tested in a reconstituted system. Moreover,immunoprecipitation of elastase extracts alkylated with [t4C] N-ethylmaleimide selected a single species of mol wt 60,000. Immunoprecipitation of in vivo radiolabeled proteins from the appropriate cell type yielded the 72,000-mol wt membrane protein irrespective of the duration of labeling, or if followed by a chase. Subsequent treatment with protease generated the 60,000-mol wt fragment. In addition, the antibody could be used to visualize reticular structures in intact cells which correspond to endoplasmic reticulum at the ultrastructural level . It is thus clear that one membrane component required in the vectorial translocation of nascent secretory (and membrane) proteins is a peptide of mol wt 72,000.
date: 1982
type: Article
type: info:eu-repo/semantics/article
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/8552/1/Meyer_1982.JCB.pdf
identifier: DOI:10.11588/heidok.00008552
identifier: urn:nbn:de:bsz:16-opus-85528
identifier:   Meyer, David I. ; Louvard, Daniel ; Dobberstein, Bernhard  (1982) Characterization of Molecules Involved in Protein Translocation Using a Specific Antibody.  The Journal of Cell Biology, 92.  pp. 579-583.      
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/8552/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng