Linked Life Data

2137824

Source:http://linkedlifedata.com/resource/pubmed/id/2137824

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1990-4-9
pubmed:abstractText
The selectivity of D2 dopamine receptor-guanine nucleotide-binding protein (G protein) coupling was studied by reconstitution techniques utilizing purified D2 dopamine receptors from bovine anterior pituitary and resolved G proteins from bovine brain, bovine pituitary, and human erythrocyte. Titration of a fixed receptor concentration with varying G protein concentrations revealed two aspects of receptor-G protein coupling. First, Gi2 appeared to couple selectively with the D2 receptor with approximately 10-fold higher affinity than any other tested Gi subtype. Second, the G proteins differed in the maximal receptor-mediated agonist stimulation of the intrinsic GTPase activity. Gi2 appeared to be maximally stimulated by agonist-receptor complex with turnover numbers of approximately 2 min-1. The other Gi subtypes, Gi1 and Gi3, could be only partially activated, resulting in maximal rates of GTPase of approximately 1 min-1. Agonist-stimulated GTPase activity was not detected in preparations containing Go from bovine brain. The differences in maximal agonist-stimulated GTPase rates observed among the Gi subtypes could be explained by differences in agonist-promoted guanyl nucleotide exchange. Both guanosine 5'-3-O-(thio)triphosphate (GTP gamma S) binding and GDP release parameters were enhanced 2-fold for the Gi2 subtype over the other Gi subtypes. These results suggest that even though several types of pertussis toxin substrate may exist in most tissues, a receptor may interact discretely with G proteins, thereby dictating signal transduction mechanisms.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4507-14
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:2137824-Animals, pubmed-meshheading:2137824-Brain Chemistry, pubmed-meshheading:2137824-Cattle, pubmed-meshheading:2137824-Erythrocytes, pubmed-meshheading:2137824-GTP Phosphohydrolases, pubmed-meshheading:2137824-GTP-Binding Proteins, pubmed-meshheading:2137824-Guanosine 5'-O-(3-Thiotriphosphate), pubmed-meshheading:2137824-Guanosine Diphosphate, pubmed-meshheading:2137824-Guanosine Triphosphate, pubmed-meshheading:2137824-Humans, pubmed-meshheading:2137824-Kinetics, pubmed-meshheading:2137824-Molecular Weight, pubmed-meshheading:2137824-Pituitary Gland, pubmed-meshheading:2137824-Receptors, Dopamine, pubmed-meshheading:2137824-Receptors, Dopamine D2, pubmed-meshheading:2137824-Rhodopsin, pubmed-meshheading:2137824-Signal Transduction, pubmed-meshheading:2137824-Thionucleotides
pubmed:year
1990
pubmed:articleTitle
Specificity of receptor-G protein interactions. Discrimination of Gi subtypes by the D2 dopamine receptor in a reconstituted system.
pubmed:affiliation
Department of Cell Biology, Howard Hughes Medical Institute, Duke University Medical Center, Durham, North Carolina 27710.
pubmed:publicationType
Journal Article, Comparative Study