کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10822719 1061700 2005 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Transmembrane helices before, during, and after insertion
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Transmembrane helices before, during, and after insertion
چکیده انگلیسی
The transmembrane (TM) helix is the fundamental structural unit of helix-bundle membrane proteins. Recent biophysical studies provide new insights into the interactions of TM helices with each other and with membrane lipid bilayers. The biological process of helix insertion is carried out by translocon complexes acting in concert with ribosomes. An electron cryo-microscopic reconstruction of these complexes reveals their architecture in new detail, and shows that the complex is constructed from four SecY/Sec61 heterotrimers and two TRAP complexes. A disulfide bridge study shows that elongating polypeptide chains pass through the pore previously identified in the X-ray structure of an archaeal SecY heterotrimer. The fundamental code used by the translocon to select polypeptide segments for insertion as TM helices has been broken. A detailed analysis of the TM amino acid distributions of helix-bundle membrane proteins of known structure recapitulates this code.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Current Opinion in Structural Biology - Volume 15, Issue 4, August 2005, Pages 378-386
نویسندگان
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