Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
1997-6-2
pubmed:abstractText
Tom70p is targeted and inserted into the mitochondrial outer membrane in the Nin-Ccyto orientation, via an NH2-terminal signal anchor sequence. The signal anchor is comprised of two domains: an NH2-terminal hydrophilic region which is positively charged (amino acids 1-10) followed by the predicted transmembrane segment (amino acids 11-29). Substitution of the NH2-terminal domain with a matrix-targeting signal caused the signal anchor to adopt the reverse orientation in the outer membrane (Ncyto-Cin) or, if presented to mitoplasts, to arrest protein translocation at the inner membrane without insertion. Physically separating the transmembrane segment from the matrix-targeting signal by moving it downstream within the protein resulted in a failure to arrest in either membrane, and consequently the protein was imported to the matrix. However, if the mean hydrophobicity of the Tom70p transmembrane segment was increased in these constructs, the protein inserted into the inner membrane with an Nin-Cout orientation. Therefore we have determined conditions that allow the Tom70p transmembrane domain to insert in either membrane, pass through both membranes, or arrest without insertion in the inner membrane. These results identify the mean hydrophobicity of potential transmembrane domains within bitopic proteins as an important determinant for insertion into the mitochondrial inner membrane.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
2
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
12057-61
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Alteration of a mitochondrial outer membrane signal anchor sequence that permits its insertion into the inner membrane. Contribution of hydrophobic residues.
pubmed:affiliation
Department of Biochemistry, McIntyre Medical Sciences Building, McGill University, Montreal, Quebec H3G 1Y6, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't