Molecular characterization of a rat alpha 2B-adrenergic receptor.
Alpha 2-adrenergic receptors comprise a heterogeneous population based on pharmacologic and molecular evidence. We have isolated a cDNA clone (pRNG alpha 2) encoding a rat alpha 2-adrenergic receptor. A rat kidney cDNA library was screened with an oligonucleotide complementary to a highly conserved region found in all biogenic amine receptors described to date. The deduced amino acid sequence displays many features of guanyl nucleotide-binding protein-coupled receptors except it does not have a consensus N-linked glycosylation site near the amino terminus. Membranes prepared from COS cells transfected with pRNG alpha 2 DNA display high affinity and saturable binding to [3H]rauwolscine (Kd = 2 nM). Competition curve data analysis shows that RNG alpha 2 protein binds to a variety of adrenergic drugs with the following rank order of potency: yohimbine greater than or equal to chlorpromazine greater than or equal to prazosin greater than or equal to clonidine greater than norepinephrine greater than or equal to oxymetazoline. RNG alpha 2 RNA accumulates in both rat kidney and neonatal rat lung (predominant species is 4000 nucleotides). When a cysteine residue (Cys-169) that is conserved among all members of the seven-transmembrane-region superfamily is changed to phenylalanine, the RNG alpha 2 protein fails to bind [3H]rauwolscine after expression in COS cells. We conclude that pRNG alpha 2 likely represents a cDNA for a rat alpha 2B-adrenergic receptor.
Zeng
D W
DW
Department of Pharmacology, University of Virginia School of Medicine, Charlottesville 22908.
Harrison
J K
JK
D'Angelo
D D
DD
Barber
C M
CM
Tucker
A L
AL
Lu
Z H
ZH
Lynch
K R
KR
D000818:Animals; D001483:Base Sequence; D001667:Binding, Competitive; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D005822:Genetic Vectors; D007668:Kidney / Q000378:metabolism; D007700:Kinetics; D008168:Lung / Q000378:metabolism; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000235:genetics* / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid
D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D011942:Receptors, Adrenergic, alpha; D004247:DNA