Linked Life Data

9486768

Source:http://linkedlifedata.com/resource/pubmed/id/9486768

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1998-3-31
pubmed:databankReference
pubmed:abstractText
Posttranslational modification of proteins by kinases and phosphatases plays an important role in the regulation of cellular signaling in general and neurochemistry in particular. This also applies to vertebrate photoreceptors where phosphorylation of rhodopsin causes uncoupling from the signal transduction cascade. Functional activity of rhodopsin is restored after substitution of the bleached photopigment 11-cisretinal and by dephosphorylation of the opsin moiety. Phosphatases type-1 and type-2A have been identified in vertebrate retinae. Recently, we have shown by molecular cloning that two isozymes of protein phosphatase type-2C (PP2C, PPM) do exist in retinal tissue. In this report, we have purified PP2Calpha and PP2Cbeta from bovine retinae. Thirty to 40% of PP2C was recovered in the cytosolic fraction. Biochemical properties of native and heterologously expressed recombinant enzymes were similar. Enzymatic activity is strictly dependent on the presence of Mg2+. Addition of Ca2+ ions inhibits Mg2+-sustained activity. Antiserum raised against a C-terminal peptide of PP2Cbeta specifically labeled the outer segments of rod photoreceptor cells. PP2C protein levels were significantly reduced in RCS rats, which develop age-dependent photoreceptor degeneration comparable to the hereditary disease retinitis pigmentosa. Although the retinal substrate(s) remain to be identified, the results suggest that PP2C modulates cellular components of the phototransduction machinery.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0360-4012
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
51
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
328-38
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:9486768-Amino Acid Sequence, pubmed-meshheading:9486768-Animals, pubmed-meshheading:9486768-Cattle, pubmed-meshheading:9486768-Immunohistochemistry, pubmed-meshheading:9486768-Isoenzymes, pubmed-meshheading:9486768-Molecular Sequence Data, pubmed-meshheading:9486768-Nerve Degeneration, pubmed-meshheading:9486768-Nerve Tissue Proteins, pubmed-meshheading:9486768-Phosphoprotein Phosphatases, pubmed-meshheading:9486768-Phosphorylation, pubmed-meshheading:9486768-Photoreceptor Cells, pubmed-meshheading:9486768-Protein Phosphatase 2, pubmed-meshheading:9486768-Rats, pubmed-meshheading:9486768-Rats, Sprague-Dawley, pubmed-meshheading:9486768-Recombinant Proteins, pubmed-meshheading:9486768-Saccharomyces cerevisiae Proteins, pubmed-meshheading:9486768-Sequence Homology, Amino Acid
pubmed:year
1998
pubmed:articleTitle
Protein phosphatase type-2C isozymes present in vertebrate retinae: purification, characterization, and localization in photoreceptors.
pubmed:affiliation
Universität, Pharmazeutische Chemie, Marburg, Germany. klumpp@pharmazie.uni-marburg.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't