Receptors

Olfactory Receptors (ORs) are the physical barriers between the environment and the brain. ORs are members of the GPCR-rhodopsin family, which is involved in cell recognition, signal transduction activation, and sense mediation. OR is made up of seven transmembrane (TM) helical domains bound by three putative extracellular loops (EL) and three putative intracellular loops (IL), an extracellular N-terminus, and an intracellular C-terminus. At the intersection of TM3 and IL2, the intracellular loop includes a conserved sequence motif, the aspartate-arginine-tyrosine (DRY) amino acid motif, which is a hallmark of GPCRs. The TM1, TM2, and TM7 are all conserved. The binding site specificity is determined by the amino acid side chains of the central TM domains, which are structurally diverse. The binding pocket of ORs has a hydrophobic environment, indicative of hydrophobic interactions between odorants and ORs. The binding specificity of ORs is influenced not only by the central TM-domains hyper-variable region, but also by the N-termini and C-termini. Both terminals are small, with only about 20 amino acids each. The conserved cysteine residues in the EL1 and EL2-loops are involved in inter- and intramolecular disulphide linkages. One of the three cysteine restudies in EL2-loop has a specific role. A metal binding site is formed by the sequence motif (HXXC[DE]) in EL2-loop. On binding with Zn(II) or Cu, the EL2-loop transforms into a -helical structure confirmation (eighth helix) (II).When an odorant with a high affinity for metal ions replaces one of the metal-ligated amino acids in the EL2-loop, ORs undergo structural rearrangement, which is necessary for the activation of G-olf proteins attached to OR receptors. On the cytoplasmic side of the TM domains, the sequence motifs KAFSTC, PMYFFL, and YRDYAM play a role in OR folding and activation. The amino acid residues on the extracellular side of TM domains are variable, indicating a wide range of possible odorant recognition sites.

OlfactionBase lists 2067 ORs from two species (Human (851) and Mus musculus (1216)).

receptors
Sr. No Receptor Organism Length Chromosome Family Sub Family UniProt GenBank #Odorants Details
1926 MOR239-5 Mus musculus 314 19 4 D Q0VDY1 NM_146678 0 View
1927 MOR214-3 Mus musculus 312 19 5 AN Q8VFV6 NM_146686 0 View
1928 MOR215-1 Mus musculus 315 19 5 AN Q8VFV4 NM_146684 0 View
1929 MOR202-9 Mus musculus 312 19 5 B Q0VEV7 NM_146697 0 View
1930 MOR202-4 Mus musculus 319 19 5 B Q8VFX2 NM_146702 0 View
1931 MOR202-7 Mus musculus 314 19 5 B Q8VFW9 NM_146699 0 View
1932 MOR202-2 Mus musculus 308 19 5 B Q8VFX4 NM_146704 0 View
1933 MOR202-3 Mus musculus 309 19 5 B Q8VFX3 NM_146703 0 View
1934 MOR202-5 Mus musculus 314 19 5 B Q8VFX1 NM_146701 0 View
1935 MOR202-34 Mus musculus 314 19 5 B Q8VEV8 NM_146303 0 View
1936 MOR202-1 Mus musculus 310 19 5 B Q8VFX5 NM_146705 0 View
1937 MOR202-6 Mus musculus 307 19 5 B Q7TQR2 NM_146700 0 View
1938 MOR202-14 Mus musculus 307 19 5 B Q8VFW2 NM_146692 0 View
1939 MOR202-17 Mus musculus 307 19 5 B Q8VFV9 NM_146689 0 View
1940 MOR202-35 Mus musculus 312 19 5 B Q8VEV7 NM_146302 0 View
1941 MOR202-13 Mus musculus 307 19 5 B Q8VFW3 NM_146693 0 View
1942 MOR202-10 Mus musculus 314 19 5 B Q7TQQ9 NM_146696 0 View
1943 MOR202-37 Mus musculus 315 19 5 B Q8VEU6 NM_146291 0 View
1944 MOR202-18 Mus musculus 315 19 5 B Q8VFQ6 NM_146636 0 View
1945 MOR202-19 Mus musculus 313 19 5 B Q8VFQ5 NM_146635 0 View
1946 MOR266-8 Mus musculus 319 19 10 Q Q8VEZ5 NM_146345 0 View
1947 MOR266-1 Mus musculus 315 19 10 Q Q8VGP8 NM_146990 0 View
1948 MOR212-1 Mus musculus 314 19 9 Q Q8VG11 NM_146741 0 View
1949 MOR212-3 Mus musculus 315 19 9 I Q8VFQ3 NM_146633 0 View
1950 MOR212-2 Mus musculus 315 19 9 I Q8VFQ4 NM_146634 0 View
Showing 1926 to 1950 of total 2067 entries