Linked Life Data

2187531

Source:http://linkedlifedata.com/resource/pubmed/id/2187531

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
15
pubmed:dateCreated
1990-6-26
pubmed:abstractText
Transducin (Gt) is a member of a family of receptor-coupled signal-transducing guanine nucleotide (GN) binding proteins (G-proteins). Light-activated rhodopsin is known to catalyze GN exchange on Gt, resulting in the formation of the active state of the Gt alpha-GTP complex. However, purified preparations of Gt have been shown to exchange GN in the absence of activated receptors [Wessling-Resnick, M., & Johnson, G. L. (1987) Biochemistry 26, 4316-4323]. To evaluate the role of rhodopsin in the activation of Gt, we studied GN-binding characteristics of different preparations of Gt. Gt preparations obtained rom the supernate of GTP-treated bovine rod outer segment (ROS) disks, followed by removal of free GTP on a Sephadex G-25 column, bound GTP gamma S at 30 degrees C in the absence of added exogenous rhodopsin with an activity of 1 mol of GTP gamma S bound/mol of Gt (Gt-I preparations). Binding of GTP gamma S to Gt-I preparations closely correlated with the activation of ROS disk cGMP phosphodiesterase. GN-binding activity of Gt-I preparations was dependent on reaction temperature, and no binding was observed at 4 degrees C. In the presence of 10 microM bleached rhodopsin, Gt-I preparations bound GTP gamma S at 4 degrees C. However, hexylagarose chromatography of Gt-I preparations led to a preparation of Gt that showed less than 0.1 mol/mol binding activity following 60-min incubation at 30 degrees C in the absence of rhodopsin (Gt-II preparations).(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3804-12
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Guanine nucleotide binding characteristics of transducin: essential role of rhodopsin for rapid exchange of guanine nucleotides.
pubmed:affiliation
Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06510.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't