Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1980-7-22
pubmed:abstractText
A light-activated GTPase that functions as a component of the rhodopsin-linked, light-activated phosphodiesterase (PDEase) system in vertebrate photoreceptors has been reported. In our efforts to purify photoreceptor GTPase we encountered another component (which we call "helper" or "H" component) whose presence is required for expression of light-activated GTPase activity. We report here the characterization of this heat-labile, macromolecular factor and that the presence of helper is absolutely required for light- and rhodopsin-dependent activation of photoreceptor GTPase. Of equal importance, we find that the "G" component (which requires the presence of H for expression of GTPase activity) can bind GTP and can support light- and GTP-dependent PDEase activation in the absence of H component. These data support a model in which GTP binding to G component is a necessary condition for PDEase activation. Hydrolysis of GTP at the G activator locus (an H-dependent activity) is a regulatory event which reverses PDEase activation. The complexity of this regulatory mechanism provides opportunities for signal modulation and amplification.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-13767412, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-165667, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-167806, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-169236, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-188466, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-200847, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-200909, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-203612, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-222967, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-227247, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-27082, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-4242925, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-4280489, http://linkedlifedata.com/resource/pubmed/commentcorrection/6103534-4341702
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0027-8424
pubmed:author
pubmed:issnType
Print
pubmed:volume
77
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1408-11
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
Additional component required for activity and reconstitution of light-activated vertebrate photoreceptor GTPase.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.