The dopamine D2 receptor: two molecular forms generated by alternative splicing.
Cloned human dopamine D2 receptor cDNA was isolated from a pituitary cDNA library and found to encode an additional 29 amino acid residues in the predicted intracellular domain between transmembrane regions 5 and 6 relative to a previously described rat brain D2 receptor. Results from polymerase chain reactions as well as in situ hybridization revealed that mRNA encoding both receptor forms is present in pituitary and brain of both rat and man. The larger form was predominant in these tissues and, as shown in the rat, expressed by dopaminergic and dopaminoceptive neurons. Analysis of the human gene showed that the additional peptide sequence is encoded by a separate exon. Hence, the two receptor forms are generated by differential splicing possibly to permit coupling to different G proteins. Both receptors expressed in cultured mammalian cells bind [3H]spiperone with high affinity and inhibit adenylyl cyclase, as expected of the D2 receptor subtype.
Dal Toso
R
R
Laboratory of Molecular Neuroendocrinology, ZMBH, Heidelberg, FRG.
Sommer
B
B
Ewert
M
M
Herb
A
A
Pritchett
D B
DB
Bach
A
A
Shivers
B D
BD
Seeburg
P H
PH
D000595:Amino Acid Sequence; D001345:Autoradiography; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D005091:Exons; D005796:Genes; D005822:Genetic Vectors; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D009693:Nucleic Acid Hybridization; D015345:Oligonucleotide Probes; D010902:Pituitary Gland / Q000378:metabolism; D010957:Plasmids; D016133:Polymerase Chain Reaction; D012326:RNA Splicing; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D011954:Receptors, Dopamine / Q000235:genetics*; D017448:Receptors, Dopamine D2; D015183:Restriction Mapping; D013462:Sulfur Radioisotopes
D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D011954:Receptors, Dopamine; D017448:Receptors, Dopamine D2; D013462:Sulfur Radioisotopes; D004247:DNA