A structure for the trimeric MHC class II-associated invariant chain transmembrane domain
UNSPECIFIED. (2002) A structure for the trimeric MHC class II-associated invariant chain transmembrane domain. Journal of Molecular Biology, 320 (5). pp. 1109-1117. ISSN 0022-2836Full text not available from this repository.
Official URL: http://dx.doi.org/10.1061/S0022-2836(02)00563-6
The major histocompatibility complex (MHC)-associated invariant chain (Ii) contains a single transmembrane domain that forms trimers. Ii is involved in the assembly of the MHC and antigen presentation, and is thus central to the function of the immune system. Here, we show by attenuated total reflectance, Fourier transform infrared (ATR-FTIR) spectroscopy that the transmembrane domain is a-helical and we provide a structural model of the transmembrane domain obtained by a combination of site-specific infrared dichroism and molecular dynamics (MD) simulations. This work resolves the backbone structure of a transmembrane peptide by multiple C-13=O-18 labelling at ten different residues. A second purely computational approach, based on MD simulations of Ii transmembrane homologous sequences, yields a similar structure that is consistent with our experimental results. The structure presented forms a left-handed coiled coil with an average helix tilt of 13(+/-6)degrees; the residue Gln47 implicated in trimer formation forms strong interhelical contacts, Thr50 points to the inside of the trimeric coil and forms a network of hydrogen bonds. (C) 2002 Elsevier Science Ltd. All rights reserved.
|Item Type:||Journal Article|
|Subjects:||Q Science > QD Chemistry|
|Journal or Publication Title:||Journal of Molecular Biology|
|Publisher:||ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD|
|Official Date:||26 July 2002|
|Number of Pages:||9|
|Page Range:||pp. 1109-1117|
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