Linked Life Data

9770355

Source:http://linkedlifedata.com/resource/pubmed/id/9770355

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1998-11-13
pubmed:abstractText
The cAMP-dependent pathway has been long presumed to play a critical role in mediating alpha-melanocyte-stimulating hormone (alpha-MSH)-induced pigmentation, but it has never been demonstrated that this pathway is obligatory. In order to determine whether the cAMP-dependent pathway is required for a alpha-MSH-induced pigmentation, we inhibited the activity of cAMP-dependent protein kinase (PKA), the main kinase mediating in this pathway, by introducing a physiologic cAMP-dependent protein kinase inhibitor (PKI) into S91 murine melanoma cells and then measuring pigment response after alpha-MSH stimulation. Cells were stably transfected either with the pMXX-PKI expression vector that encodes the active part of PKI (the amino terminal 1-31 amino acids) under a metallothionein-inducible promoter and the pSV2-Neo expression vector alone. As expected, treatment of transfected cells with 1 microM CdCl2 for 24 h induced the expression of PKI mRNA in cells transfected with both vectors, but not in cells transfected with the pSV2-Neo expression vector alone. Subsequent treatment of these transfected cells with alpha-MSH for 5-6 days in the continual presence of 1 microM CdCl2 resulted in inhibition of PKA activity by 30-40% in cells expressing PKI. Parallel measurements revealed that alpha-MSH-increased melanin content five- to six-fold in control cells transfected with pSV2-Neo alone, while there was only a two-fold increase in PKI-expressing cells, a 40-50% inhibition in alpha-MSH-induced total melanin content. alpha-MSH-induced tyrosinase activity and tyrosinase mRNA and protein levels measured in parallel were also inhibited by 40-50% in PKI-expressing cells compared to control cells transfected with pSV2-Neo alone. Together, these results demonstrate for the first time that activation of PKA through the cAMP-dependent pathway is required for optimal alpha-MSH-induced pigmentation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0014-4827
pubmed:author
pubmed:copyrightInfo
Copyright 1998 Academic Press.
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
244
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
117-24
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Activation of cAMP-dependent protein kinase is required for optimal alpha-melanocyte-stimulating hormone-induced pigmentation.
pubmed:affiliation
Department of Dermatology, Boston University School of Medicine, 80 East Concord Street, Boston, Massachusetts, 02118, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't