Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2008-12-5
pubmed:abstractText
Tumor protein D52 is expressed at relatively high levels in cells within the gastrointestinal tract that undergo classical exocytosis and is overexpressed in several cancers. Current evidence supports a role for D52 in the regulation of vesicular trafficking. D52 function(s) are regulated by calcium-dependent phosphorylation; however, the intracellular mechanisms that mediate this process are not well characterized. The goal of this study was to identify the calcium-dependent phosphorylation site(s) in D52 and to characterize the protein kinase(s) that mediate this phosphorylation. Using mass spectrometry and site-directed mutagenesis, we identified a single amino acid residue, S(136), that undergoes increased phosphorylation upon elevation of intracellular Ca(2+) concentration. A phosphospecific antibody (pS(136)) was produced and used to characterize D52 kinase activity in gastric mucosal, colonic T84, and HEK293 cells. By using D52 as a substrate, a protein kinase with a molecular weight (M(r)) of approximately 50 kDa was identified with "in gel" assays. This kinase comigrated with rat brain calcium/calmodulin-dependent protein kinase (CAMK2)alpha cross-reacted with pan-specific CAMK2 antibodies as well as with anti-active CAMK2 (pT(286/287)) antibody when activated. Carbachol-stimulated phosphorylation of S(136) was inhibited by the CAMK2 inhibitor KN93 (IC(50) 38 microM) and by the calmodulin antagonist W7 (IC(50) 3.3 nM). A previously uncharacterized CAMK2 isoform, CAMK2delta6, which has the same domain structure and M(r) as CAM2alpha, was identified in gastric mucosa by RT-PCR. The cloned, expressed protein comigrated with D52 kinase and colocalized with D52 protein in T84 and HEK293 cells. These findings support a role for CAMK2delta6 in the mediation of D52 phosphorylation.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-10583399, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-10806114, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-11077048, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-11264466, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-11384973, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-11549320, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-11867640, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-11931644, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-12105190, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-12432067, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-12507466, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-12893633, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-1332720, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-14594813, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-14644494, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-14977633, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-15084659, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-15203023, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-15358133, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-15458922, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-15555543, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-15576473, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-15790763, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-16054524, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-16278279, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-16368898, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-16631610, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-17081983, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-18483181, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-1963655, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-2155222, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-2174171, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-2557021, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-3379827, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-3741886, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-7796418, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-8130281, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-8280094, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-8532140, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-8632896, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-8702730, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-8940165, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-9864285, http://linkedlifedata.com/resource/pubmed/commentcorrection/18832449-9915840
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0193-1857
pubmed:author
pubmed:issnType
Print
pubmed:volume
295
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
G1159-72
pubmed:dateRevised
2010-9-21
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Calcium/calmodulin-dependent phosphorylation of tumor protein D52 on serine residue 136 may be mediated by CAMK2delta6.
pubmed:affiliation
Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA 30912, USA. cchew@mcg.edu
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural