Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1986-8-8
pubmed:abstractText
Secretory proteins are synthesized on ribosomes bound to the membrane of the endoplasmic reticulum (ER). After the selection of polysomes synthesizing secretory proteins and their direction to the membrane of the ER via signal recognition particle (SRP) and docking protein respectively, the polysomes become bound to the ER membrane via an unknown, protein-mediated mechanism. To identify proteins involved in protein translocation, beyond the (SRP-docking protein-mediated) recognition step, controlled proteolysis was used to functionally inactivate rough microsomes that had previously been depleted of docking protein. As the membranes were treated with increasing levels of protease, they lost their ability to be functionally reconstituted with the active cytoplasmic fragment of docking protein (DPf). This functional inactivation did not correlate with a loss of either signal peptidase activity, nor with the ability of the DPf to reassociate with the membrane. It did correlate, however, with a loss of the ability of the microsomes to bind ribosomes. Ribophorins are putative ribosome-binding proteins. Immunoblots developed with monoclonal antibodies against canine ribophorins I and II demonstrated that no correlation exists between the protease-induced inability to bind ribosomes and the integrity of the ribophorins. Ribophorin I was 85% resistant and ribophorin II 100% resistant to the levels of protease needed to totally eliminate ribosome binding. Moreover, no direct association was found between ribophorins and ribosomes; upon detergent solubilization at low salt concentrations, ribophorins could be sedimented in the presence or absence of ribosomes. Finally, the alkylating agent N-ethylmaleimide was shown to be capable of inhibiting translocation (beyond the SRP-docking protein-mediated recognition step), but had no affect on the ability of ribosomes to bind to ER membranes. We conclude that potentially two additional proteinaceous components, as yet unidentified, are involved in protein translocation. One is protease sensitive and possibly involved in ribosome binding, the other is N-ethylmaleimide sensitive and of unknown function.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-1096303, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-109833, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-2409124, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-2410409, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-271987, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-2992801, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-3021646, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-3896234, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-3919014, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-4018097, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-4048938, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-418074, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-4449120, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-4512933, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-468113, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-4682341, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-4961313, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-4961331, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-5000815, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-5158923, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-5284428, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6088076, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6234018, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6249584, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6258987, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6266278, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6292236, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6317198, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-649658, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6501423, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6501424, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6563037, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6656642, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6656648, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-6995850, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-7000796, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-7068762, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-7084228, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-7088152, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-7287643, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-7309795, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-7309796, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-7430254, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-811671, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-880237, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-942051, http://linkedlifedata.com/resource/pubmed/commentcorrection/3087996-96350
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9525
pubmed:author
pubmed:issnType
Print
pubmed:volume
103
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
241-53
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Characterization of secretory protein translocation: ribosome-membrane interaction in endoplasmic reticulum.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't