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Transmembrane glycine zippers: physiological and pathological roles in membrane proteins.

ABSTRACT: We have observed a common sequence motif in membrane proteins, which we call a glycine zipper. Glycine zipper motifs are strongly overrepresented and conserved in membrane protein sequences, and mutations in glycine zipper motifs are deleterious to function in many cases. The glycine zipper has a significant structural impact, engendering a strong driving force for right-handed packing against a neighboring helix. Thus, the presence of a glycine zipper motif leads directly to testable structural hypotheses, particularly for a subclass of glycine zipper proteins that form channels. For example, we suggest that the membrane pores formed by the amyloid-beta peptide in vitro are constructed by glycine zipper packing and find that mutations in the glycine zipper motif block channel formation. Our findings highlight an important structural motif in a wide variety of normal and pathological processes.

SUBMITTER: Kim S

PROVIDER: S-EPMC1242278 | biostudies-literature | 2005 Oct

REPOSITORIES: biostudies-literature

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Transmembrane glycine zippers: physiological and pathological roles in membrane proteins.

Kim Sanguk S Jeon Tae-Joon TJ Oberai Amit A Yang Duan D Schmidt Jacob J JJ Bowie James U JU

Proceedings of the National Academy of Sciences of the United States of America 20050922 40

We have observed a common sequence motif in membrane proteins, which we call a glycine zipper. Glycine zipper motifs are strongly overrepresented and conserved in membrane protein sequences, and mutations in glycine zipper motifs are deleterious to function in many cases. The glycine zipper has a significant structural impact, engendering a strong driving force for right-handed packing against a neighboring helix. Thus, the presence of a glycine zipper motif leads directly to testable structural ...[more]

PMID: 16179394

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