Publication Date:
2011-06-24
Description:
The biogenic amine histamine is an important pharmacological mediator involved in pathophysiological processes such as allergies and inflammations. Histamine H(1) receptor (H(1)R) antagonists are very effective drugs alleviating the symptoms of allergic reactions. Here we show the crystal structure of the H(1)R complex with doxepin, a first-generation H(1)R antagonist. Doxepin sits deep in the ligand-binding pocket and directly interacts with Trp 428(6.48), a highly conserved key residue in G-protein-coupled-receptor activation. This well-conserved pocket with mostly hydrophobic nature contributes to the low selectivity of the first-generation compounds. The pocket is associated with an anion-binding region occupied by a phosphate ion. Docking of various second-generation H(1)R antagonists reveals that the unique carboxyl group present in this class of compounds interacts with Lys 191(5.39) and/or Lys 179(ECL2), both of which form part of the anion-binding region. This region is not conserved in other aminergic receptors, demonstrating how minor differences in receptors lead to pronounced selectivity differences with small molecules. Our study sheds light on the molecular basis of H(1)R antagonist specificity against H(1)R.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3131495/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3131495/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Shimamura, Tatsuro -- Shiroishi, Mitsunori -- Weyand, Simone -- Tsujimoto, Hirokazu -- Winter, Graeme -- Katritch, Vsevolod -- Abagyan, Ruben -- Cherezov, Vadim -- Liu, Wei -- Han, Gye Won -- Kobayashi, Takuya -- Stevens, Raymond C -- Iwata, So -- 062164/ Z/00/Z/Wellcome Trust/United Kingdom -- BB/G023425/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- P50 GM073197/GM/NIGMS NIH HHS/ -- P50 GM073197-07/GM/NIGMS NIH HHS/ -- R01 GM071872/GM/NIGMS NIH HHS/ -- R01 GM071872-02/GM/NIGMS NIH HHS/ -- R01 GM071872-08/GM/NIGMS NIH HHS/ -- R01 GM089857/GM/NIGMS NIH HHS/ -- U54 GM094618/GM/NIGMS NIH HHS/ -- U54 GM094618-01/GM/NIGMS NIH HHS/ -- England -- Nature. 2011 Jun 22;475(7354):65-70. doi: 10.1038/nature10236.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Human Receptor Crystallography Project, ERATO, Japan Science and Technology Agency, Kyoto 606-8501, Japan.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21697825" target="_blank"〉PubMed〈/a〉
Keywords:
Binding Sites
;
Crystallography, X-Ray
;
Doxepin/chemistry/*metabolism
;
Histamine Antagonists/chemistry/*metabolism
;
Humans
;
Hydrophobic and Hydrophilic Interactions
;
Isomerism
;
Ligands
;
Models, Molecular
;
Phosphates/chemistry/metabolism
;
Protein Binding
;
Protein Conformation
;
Receptors, Adrenergic, beta-2/chemistry
;
Receptors, Dopamine D3/chemistry
;
Receptors, Histamine H1/*chemistry/*metabolism
;
Substrate Specificity
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
