The differences between these two binding sites are demonstrated in Figure 2, which shows the structures of the insulin receptor tyrosine kinase (IRK) and the serine/threonine kinase Akt crystallized with ATP mimics bound to the ATP binding pocket and peptidic ligands bound to the substrate site.
Moreover, the zinc-dependent binding of purified Zur protein to double-stranded 40-mer oligonucleotides containing candidate Zur-binding sites was demonstrated in vitro by DNA band shift assays.
Already at the turn of the centuries, the presence of GnRH-binding sites was demonstrated in uterine myomas, suggesting direct effect of GnRH analogues upon the uterine tissues [ 19].
Highly efficient and specific displacements of both ligands from their endogenous mitochondrial binding sites were also demonstrated (data not shown).
Furthermore, direct interaction between delphinidin and ERα activator site is demonstrated using both binding assay and docking.
When selective V1R and V2R radioligands with in vitro auto-radiography were used to study V1R and V2R binding sites, no binding was demonstrated on endothelium or liver, where DDAVP might influence clotting factor release, or in the brain, spinal cord, sympathetic ganglia, heart or vascular smooth muscle – regions where DDAVP might cause vasodilation [ 46].
Moreover, direct interaction between TR alpha and the active form of SREBP1 has been demonstrated when their binding sites are closely located in the promoter of the chicken acetyl-CoA carboxylase-α gene [ 30].
Upon being saturated with Ca2+, these two N-terminal low-affinity Ca2+ binding sites have been demonstrated to activate CN by direct CNB/CNA interaction and by facilitating CaM/CNA binding.
