Linked Life Data

15811380

Source:http://linkedlifedata.com/resource/pubmed/id/15811380

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2005-4-6
pubmed:abstractText
The mammalian Sec61 complex forms a protein translocation channel whose function depends upon its interaction with the ribosome and with membrane proteins of the endoplasmic reticulum (ER). To study these interactions, we determined structures of "native" ribosome-channel complexes derived from ER membranes. We find that the ribosome is linked to the channel by seven connections, but the junction may still provide a path for domains of nascent membrane proteins to move into the cytoplasm. In addition, the native channel is significantly larger than a channel formed by the Sec61 complex, due to the presence of a second membrane protein. We identified this component as TRAP, the translocon-associated protein complex. TRAP interacts with Sec61 through its transmembrane domain and has a prominent lumenal domain. The presence of TRAP in the native channel indicates that it may play a general role in translocation. Crystal structures of two Sec61 homologues were used to model the channel. This analysis indicates that there are four Sec61 complexes and two TRAP molecules in each native channel. Thus, we suggest that a single Sec61 complex may form a conduit for translocating polypeptides, while three copies of Sec61 play a structural role or recruit accessory factors such as TRAP.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
29
pubmed:volume
348
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
445-57
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Architecture of the ribosome-channel complex derived from native membranes.
pubmed:affiliation
Department of Physiology and Biophysics, Boston University School of Medicine, 700 Albany St., Boston, MA 02118-2526, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't