Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2008-5-19
pubmed:abstractText
Centrins are Ca2+-binding EF-hand proteins. All four known centrin isoforms are expressed in the ciliary apparatus of photoreceptor cells. Cen1p and Cen2p bind to the visual G-protein transducin in a strictly Ca2+-dependent way, which is thought to regulate light driven movements of transducin between photoreceptor cell compartments. These relatively slow motile processes represent a novel paradigm in light adaptation of photoreceptor cells. Here we validated specific phosphorylation as a novel regulator of centrins in photoreceptors. Centrins were differentially phosphorylated during photoreceptor dark adaptation. Inhibitor treatments revealed protein kinase CK2 as the major protein kinase mediating phosphorylation of Cen1p, Cen2p and Cen4p, but not Cen3p, at a specific target sequence. CK2 and ciliary centrins co-localize in the photoreceptor cilium. Direct binding of CK2 and centrins to ciliary microtubules may spatially integrate the enzyme-substrate specificity in the cilium. Kinetic light-scattering assays revealed decreased binding affinities of phosphorylated centrins to transducin. Furthermore, we show that this decrease is based on the reduction of Ca2+-binding affinities of centrins. Present data describe a novel regulatory mechanism of reciprocal regulation of stimulus dependent distribution of signaling molecules.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:volume
1783
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1248-60
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:18269917-Animals, pubmed-meshheading:18269917-Blotting, Western, pubmed-meshheading:18269917-Calcium, pubmed-meshheading:18269917-Calcium-Binding Proteins, pubmed-meshheading:18269917-Casein Kinase II, pubmed-meshheading:18269917-Cattle, pubmed-meshheading:18269917-Chromosomal Proteins, Non-Histone, pubmed-meshheading:18269917-Cilia, pubmed-meshheading:18269917-Dark Adaptation, pubmed-meshheading:18269917-Fluorescent Antibody Technique, Indirect, pubmed-meshheading:18269917-Light, pubmed-meshheading:18269917-Mass Spectrometry, pubmed-meshheading:18269917-Mice, pubmed-meshheading:18269917-Mice, Inbred C57BL, pubmed-meshheading:18269917-Microscopy, Immunoelectron, pubmed-meshheading:18269917-Microtubules, pubmed-meshheading:18269917-Phosphorylation, pubmed-meshheading:18269917-Photoreceptor Cells, Vertebrate, pubmed-meshheading:18269917-Protein Binding, pubmed-meshheading:18269917-Rats, pubmed-meshheading:18269917-Rats, Sprague-Dawley, pubmed-meshheading:18269917-Substrate Specificity, pubmed-meshheading:18269917-Transducin
pubmed:year
2008
pubmed:articleTitle
Light-dependent CK2-mediated phosphorylation of centrins regulates complex formation with visual G-protein.
pubmed:affiliation
Zell-und Matrixbiologie, Institut für Zoologie, Johannes Gutenberg-Universität Mainz, Müllerweg 6, D-55099 Mainz, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't