Evidence for hetero-association of transmembrane helices of integrins.
Integrins are important transmembrane cell-surface receptors, which mediate interactions of the cell with other cells or the extracellular matrix. Integrins are heterodimers composed of an alpha- and a beta-subunit. They can switch between different activation states depending on intra- or extracellular signals. Inside/out and outside/in signaling is mediated via integrins across the membrane. A biologically important and yet still unanswered question is the role of the transmembrane domains in the signaling event. Here it is shown by simulated annealing/molecular dynamics calculations that recently published structural data of the cytoplasmic domains of integrin alphaIIbbeta3 are supporting a structure with interacting transmembrane helices. This corroborates a model of transmembrane domains that are actively involved in the transmembrane signaling event.
Gottschalk
Kay-Eberhard
KE
Department of Biological Chemistry, Weizmann Institute of Science, Herzl St 1, 76100 Rehovot, Israel.
Kessler
Horst
H
D000595:Amino Acid Sequence; D001665:Binding Sites; D002448:Cell Adhesion / Q000502:physiology; D002462:Cell Membrane / Q000502:physiology*; D016023:Integrins / Q000737:chemistry* / Q000502:physiology*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D021122:Protein Subunits / Q000737:chemistry; D015398:Signal Transduction
D016023:Integrins; D021122:Protein Subunits