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Integrin ?1 has a long helix, extending from the transmembrane region to the cytoplasmic tail in detergent micelles.

ABSTRACT: Integrin proteins are very important adhesion receptors that mediate cell-cell and cell-extracellular matrix interactions. They play essential roles in cell signaling and the regulation of cellular shape, motility, and the cell cycle. Here, the transmembrane and cytoplasmic (TMC) domains of integrin ?1 and ?1 were over-expressed and purified in detergent micelles. The structure and backbone relaxations of ?1-TMC in LDAO micelles were determined and analyzed using solution NMR. A long helix, extending from the transmembrane region to the cytoplasmic tail, was observed in ?1-TMC. Structural comparisons of ?1-TMC with reported ?IIb-TMC domains indicated different conformations in the transmembrane regions and cytoplasmic tails. An NMR titration experiment indicated weak interactions between ?1-TMC and ?1-TMC through several ?1-TMC residues located at its N-terminal juxta-transmembrane region and C-terminal extended helix region.

SUBMITTER: Lai C

PROVIDER: S-EPMC3639902 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Integrin α1 has a long helix, extending from the transmembrane region to the cytoplasmic tail in detergent micelles.

Lai Chaohua C Liu Xiaoxi X Tian Changlin C Wu Fangming F

PloS one 20130430 4

Integrin proteins are very important adhesion receptors that mediate cell-cell and cell-extracellular matrix interactions. They play essential roles in cell signaling and the regulation of cellular shape, motility, and the cell cycle. Here, the transmembrane and cytoplasmic (TMC) domains of integrin α1 and β1 were over-expressed and purified in detergent micelles. The structure and backbone relaxations of α1-TMC in LDAO micelles were determined and analyzed using solution NMR. A long helix, exte ...[more]

PMID: 23646163

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