Interaction of tachykinins with phospholipid membranes: A neutron diffraction study
Abstract
Tachykinins are a group of peptides which bind to G-protein-coupled receptors. Receptor affinity appears to depend on different secondary structures of tachykinin which share the same hydrophobic carboxy-terminal sequence, FXGLM. Receptor activation is thought to be due to the carboxy-terminal submerging into the bilayer and the amino-terminal binding on the surface. Binding of tachykinins to phospholipid bilayers may take place both on the aqueous membrane surface and in the hydrophobic region. The two-state equilibrium appears to depend on the surface charge of the membrane. Deuterating substance P and neurokinin A at their carboxy-terminals, our results show two populations of label for each peptide. One is very close to the water-hydrocarbon interface, the other some 13 Å deeper. We report that the bilayer location of the two tachykinins is remarkably similar, thereby inferring that receptor specifity must be controlled by finer levels of structure.
- Publication:
-
Physica B Condensed Matter
- Pub Date:
- 1997
- DOI:
- 10.1016/S0921-4526(97)00811-9
- Bibcode:
- 1997PhyB..241.1144D