PMID- 10051546
OWN - NLM
STAT- MEDLINE
DCOM- 19990325
LR  - 20210223
IS  - 0026-895X (Print)
IS  - 0026-895X (Linking)
VI  - 55
IP  - 3
DP  - 1999 Mar
TI  - Role of a conserved lysine residue in the peripheral cannabinoid receptor (CB2): 
      evidence for subtype specificity.
PG  - 605-13
AB  - The human cannabinoid receptors, central cannabinoid receptor (CB1) and
      peripheral cannabinoid receptor (CB2), share only 44% amino acid identity
      overall, yet most ligands do not discriminate between receptor subtypes.
      Site-directed mutagenesis was employed as a means of mapping the ligand
      recognition site for the human CB2 cannabinoid receptor. A lysine residue in the 
      third transmembrane domain of the CB2 receptor (K109), which is conserved between
      the CB1 and CB2 receptors, was mutated to alanine or arginine to determine the
      role of this charged amino acid in receptor function. The analogous mutation in
      the CB1 receptor (K192A) was found to be crucial for recognition of several
      cannabinoid compounds excluding (R)-(+)-[2,
      3-dihydro-5-methyl-3-[(4-morpholinyl)methyl]pyrrolo[1,2,3-de]-1,
      4-benzoxazin-6-yl](1-naphthalenyl)methanone (WIN 55,212-2). In contrast, in human
      embryonic kidney (HEK)-293 cells expressing the mutant or wild-type CB2
      receptors, we found no significant differences in either the binding profile of
      several cannabinoid ligands nor in inhibition of cAMP accumulation. We identified
      a high-affinity site for (-)-3-[2-hydroxyl-4-(1,
      1-dimethylheptyl)phenyl]-4-[3-hydroxyl propyl] cyclohexan-1-ol (CP-55,940) in the
      region of helices 3, 6, and 7, with S3.31(112), T3.35(116), and N7.49(295) in the
      K109A mutant using molecular modeling. The serine residue, unique to the CB2
      receptor, was then mutated to glycine in the K109A mutant. This double mutant,
      K109AS112G, retains the ability to bind aminoalkylindoles but loses affinity for 
      classical cannabinoids, as predicted by the molecular model. Distinct cellular
      localization of the mutant receptors observed with immunofluorescence also
      suggests differences in receptor function. In summary, we identified amino acid
      residues in the CB2 receptor that could lead to subtype specificity.
FAU - Tao, Q
AU  - Tao Q
AD  - Department of Pharmacology, Virginia Commonwealth University, Richmond
      23298-0524, USA.
FAU - McAllister, S D
AU  - McAllister SD
FAU - Andreassi, J
AU  - Andreassi J
FAU - Nowell, K W
AU  - Nowell KW
FAU - Cabral, G A
AU  - Cabral GA
FAU - Hurst, D P
AU  - Hurst DP
FAU - Bachtel, K
AU  - Bachtel K
FAU - Ekman, M C
AU  - Ekman MC
FAU - Reggio, P H
AU  - Reggio PH
FAU - Abood, M E
AU  - Abood ME
LA  - eng
GR  - DA-05274/DA/NIDA NIH HHS/United States
GR  - DA-07027/DA/NIDA NIH HHS/United States
GR  - DA-09978/DA/NIDA NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Mol Pharmacol
JT  - Molecular pharmacology
JID - 0035623
RN  - 0 (Benzoxazines)
RN  - 0 (Cyclohexanols)
RN  - 0 (Ligands)
RN  - 0 (Morpholines)
RN  - 0 (Naphthalenes)
RN  - 0 (Receptors, Cannabinoid)
RN  - 0 (Receptors, Drug)
RN  - 5H31GI9502
      ((3R)-((2,3-dihydro-5-methyl-3-((4-morpholinyl)methyl)pyrrolo-(1,2,3-de)-1,4-benz
      oxazin-6-yl)(1-naphthalenyl))methanone)
RN  - 83003-12-7
      (3-(2-hydroxy-4-(1,1-dimethylheptyl)phenyl)-4-(3-hydroxypropyl)cyclohexanol)
RN  - K3Z4F929H6 (Lysine)
RN  - OF5P57N2ZX (Alanine)
SB  - IM
MH  - Alanine/physiology
MH  - Benzoxazines
MH  - Cell Line
MH  - Cyclohexanols/pharmacology
MH  - Fluorescent Antibody Technique
MH  - Humans
MH  - Ligands
MH  - Lysine/*physiology
MH  - Models, Molecular
MH  - Morpholines/pharmacology
MH  - Mutation
MH  - Naphthalenes/pharmacology
MH  - Receptors, Cannabinoid
MH  - Receptors, Drug/classification/drug effects/*metabolism
MH  - Signal Transduction
EDAT- 1999/03/03 00:00
MHDA- 1999/03/03 00:01
CRDT- 1999/03/03 00:00
PHST- 1999/03/03 00:00 [pubmed]
PHST- 1999/03/03 00:01 [medline]
PHST- 1999/03/03 00:00 [entrez]
PST - ppublish
SO  - Mol Pharmacol. 1999 Mar;55(3):605-13.