Results
We resolved two distinct dimeric structures of GHR TMD coexisting in membrane-mimicking micellar environment and providing left- and right-handed helix-helix association
via different dimerization motifs. Based on the available mutagenesis data, the conformations correspond to the dormant and active receptor states and are distinguished by cis-trans isomerization of Phe-Pro
266 bond in the transmembrane helix entry. Molecular dynamic relaxations of the structures in lipid bilayer revealed the role of the proline residue in functionally significant rearrangements of the adjacent juxtamembrane region supporting alternation between protein-protein and protein-lipid interactions of this region that can be triggered by ligand binding. Also, the importance of juxtamembrane S
![/>S bonding for signal persistency, and somewhat unusual aspects of transmembrane region interaction with water molecules were demonstrated.</div><div id=](https://sdfestaticassets-us-east-1.sciencedirectassets.com/shared-assets/16/entities/sbnd)
Conclusions
Two alternative dimeric structures of GHR TMD attributed to dormant and active receptor states interchange
via allosteric rearrangements of transmembrane helices and extracellular juxtamembrane regions that support coordination between protein-protein and protein-lipid interactions.