Viral Membrane Protein Topology Is Dictated by Multiple Determinants in Its Sequence

JOURNAL OF MOLECULAR BIOLOGY

卷:387

Article

Sauri, Ana¹  Tamborero, Silvia¹  Martinez-Gil, Luis¹  Johnson, Arthur E.^2,3,4  Mingarro, Ismael¹ 

[1] Univ Valencia, Dept Bioquim & Biol Mol, E-46100 Burjassot, Spain

[2] Texas A&M Hlth Sci Ctr, Dept Mol & Cellular Med, College Stn, TX 77843 USA

[3] Texas A&M Univ, Dept Biochem & Biophys, College Stn, TX 77843 USA

[4] Texas A&M Univ, Dept Chem, College Stn, TX 77843 USA

关键词: endoplasmic reticulum;    membrane topology;    translocon;    transmembrane segment;    viral protein;   

DOI  :  10.1016/j.jmb.2009.01.063

来源: Elsevier

【 摘 要 】

The targeting, insertion, and topology of membrane proteins have been extensively studied in both prokaryotes and eukaryotes. However, the mechanisms used by viral membrane proteins to generate the correct topology within cellular membranes are less well understood. Here, the effect of flanking charges and the hydrophobicity of the N-terminal hydrophobic segment on viral membrane protein topogenesis are examined systematically. Experimental data reveal that the classical topological determinants have only a minor effect on the overall topology of p9, a plant viral movement protein. Since only a few individual sequence alterations cause an inversion of p9 topology, its topological stability is robust. This result further indicates that the protein has multiple, and perhaps redundant, structural features that ensure that it always adopts the same topology. These critical topogenic sequences appear to be recognized and acted upon from the initial stages of protein biosynthesis, even before the ribosome ends protein translation. (C) 2009 Elsevier Ltd. All rights reserved.

【 授权许可】

Free