Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
2005-3-28
pubmed:abstractText
Rod phosphodiesterase (PDE6) is the central effector enzyme in vertebrate visual transduction. Holo-PDE6 consists of two similar catalytic subunits (Palphabeta) and two identical inhibitory subunits (Pgamma). Palphabeta is the only heterodimer in the PDE superfamily, yet its significance for the function of PDE6 is poorly understood. An unequal interaction of Pgamma with Pbeta as compared with Palpha in the PDE6 complex has not been reported. We investigated the interaction interface between full-length Pgamma and Palphabeta, by differentiating Pgamma interaction with each individual Palphabeta subunit through radiolabel transfer from various positions throughout the entire Pgamma molecule. The efficiency of radiolabel transfer indicates that the close vicinity of serine 40 on Pgamma makes a major contribution to the interaction with Palphabeta. In addition, a striking asymmetry of interaction between the Pgamma polycationic region and the Palphabeta subunits was observed when the stoichiometry of Pgamma versus the Palphabeta dimer was below 2. Preferential photolabeling on Pbeta from Pgamma position 40 and on Palpha from position 30 increased while lowering the Pgamma/Palphabeta ratio, but diminished when the Pgamma/Palphabeta ratio was over 2. Our finding leads to the conclusion that two classes of Pgamma binding sites exist on Palphabeta, each composed of GAF domains in both Palpha and Pbeta, differing from the conventional models suggesting that each Pgamma binds only one of the Palphabeta catalytic subunits. This new model leads to insight into how the unique Palphabeta heterodimer contributes to the sophisticated regulation in visual transduction through interaction with Pgamma.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
280
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
12585-92
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:15668239-3',5'-Cyclic-GMP Phosphodiesterases, pubmed-meshheading:15668239-Animals, pubmed-meshheading:15668239-Biotin, pubmed-meshheading:15668239-Blotting, Western, pubmed-meshheading:15668239-Catalysis, pubmed-meshheading:15668239-Catalytic Domain, pubmed-meshheading:15668239-Cattle, pubmed-meshheading:15668239-Cross-Linking Reagents, pubmed-meshheading:15668239-Cyclic Nucleotide Phosphodiesterases, Type 6, pubmed-meshheading:15668239-Cysteine, pubmed-meshheading:15668239-Dimerization, pubmed-meshheading:15668239-Dose-Response Relationship, Drug, pubmed-meshheading:15668239-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:15668239-Eye Proteins, pubmed-meshheading:15668239-Light, pubmed-meshheading:15668239-Mass Spectrometry, pubmed-meshheading:15668239-Models, Biological, pubmed-meshheading:15668239-Models, Chemical, pubmed-meshheading:15668239-Peptides, pubmed-meshheading:15668239-Phosphoric Diester Hydrolases, pubmed-meshheading:15668239-Protein Binding, pubmed-meshheading:15668239-Protein Structure, Tertiary, pubmed-meshheading:15668239-Retinal Rod Photoreceptor Cells, pubmed-meshheading:15668239-Serine, pubmed-meshheading:15668239-Ultraviolet Rays, pubmed-meshheading:15668239-Vision, Ocular
pubmed:year
2005
pubmed:articleTitle
Asymmetric interaction between rod cyclic GMP phosphodiesterase gamma subunits and alphabeta subunits.
pubmed:affiliation
Department of Pharmacology, University of Wisconsin Medical School, Madison, Wisconsin 53706, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.