Primary Citation of Related Structures:   5UEN
PubMed Abstract: 
The adenosine A 1 receptor (A 1 -AR) is a G-protein-coupled receptor that plays a vital role in cardiac, renal, and neuronal processes but remains poorly targeted by current drugs. We determined a 3.2 Å crystal structure of the A 1 -AR bound to the selective covalent antagonist, DU172, and identified striking differences to the previously solved adenosine A 2A receptor (A 2A -AR) structure ...
The adenosine A 1 receptor (A 1 -AR) is a G-protein-coupled receptor that plays a vital role in cardiac, renal, and neuronal processes but remains poorly targeted by current drugs. We determined a 3.2 Å crystal structure of the A 1 -AR bound to the selective covalent antagonist, DU172, and identified striking differences to the previously solved adenosine A 2A receptor (A 2A -AR) structure. Mutational and computational analysis of A 1 -AR revealed a distinct conformation of the second extracellular loop and a wider extracellular cavity with a secondary binding pocket that can accommodate orthosteric and allosteric ligands. We propose that conformational differences in these regions, rather than amino-acid divergence, underlie drug selectivity between these adenosine receptor subtypes. Our findings provide a molecular basis for AR subtype selectivity with implications for understanding the mechanisms governing allosteric modulation of these receptors, allowing the design of more selective agents for the treatment of ischemia-reperfusion injury, renal pathologies, and neuropathic pain.
Organizational Affiliation: 
Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia. Electronic address: arthur.christopoulos@monash.edu.
4-{[3-(8-cyclohexyl-2,6-dioxo-1-propyl-1,2,6,7-tetrahydro-3H-purin-3-yl)propyl]carbamoyl}benzene-1-sulfonyl fluoride C24 H30 F N5 O5 S KAJVJPLKXGLLDA-UHFFFAOYSA-N