By revealing significant differences in the number and location of negatively charged residues, especially in the extracellular loop (EL) region, visual inspection of the crystal structures of δ-OR, μ-OR, and κ-OR provided the rationale for studying whether sodium may follow different binding pathways in these receptors.
Rapid sodium permeation was observed exclusively from the extracellular milieu, and following similar binding pathways in all three ligand-free OR systems, notwithstanding extra densities of sodium observed near nonconserved residues of κ-OR and δ-OR, but not in μ-OR.
The role of the internal cavities on ligand binding pathways has been studied in mutants of HbI.
Nutrient intake may affect hormone transport in the blood, activity of peripheral tissues, binding to receptors, and neural pathways in the regulation of endocrine hormones (Leatherland et al. 1984).
In addition, multiple binding pathways of cations to a two-layered 15-mer thrombin-binding quadruplex aptamer have been shown with the use of a sum of microsecond molecular simulation (Reshetnikov et al., 2011).
Clearly, the binding of Dpo4 to DNA is a complex process, and while the FRET data described here provide new insight into an early conformational change in the binding pathway, further investigation is necessary to fully elucidate the binding mechanism.
Moreover, it remains still unknown whether GLP-1 treatment activates the protective, anti-neurodegenerative cAMP response element binding protein (CREB) pathway in the brain in vivo, and whether activation leads to observable increases in protective, anti-neurodegenerative proteins.
Initially this finding was thought to support the postulate that the C136 Hg Cys558′ complex was a key intermediate in the binding pathway.
The Ca2+ transporter molecule, ATP2A, and the troponin proteins, are involved in the Ca2+ binding pathway that leads to muscle contraction [ 102, 103].
Seven genes (HIRA, SOX2, PRKCB, ING2, TP63, BCL6 and PAX3) in this study were enriched in chromatin binding pathway (GO: 0003682) (P =1.12E-04 which are worthy of being investigated in more detail in future studies.
