Linked Life Data

2177842

Source:http://linkedlifedata.com/resource/pubmed/id/2177842

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1991-3-11
pubmed:abstractText
Many peripheral tissues express the proopiomelanocortin (POMC) gene as an 800-base mRNA that lacks the 5' end of the 1200-base pituitary transcript. The missing region encodes the peptide signal sequence, and thus, it is unlikely that any translation product would be secreted. We have found that a RNA transcript equivalent to this short message, generated by transcription in vitro from a T7 polymerase promoter, is translatable in a rabbit reticulocyte lysate, generating peptides of 27.5, 22.5, and 15.5 kD. None of these peptides appears to be processed or protected from proteinase-K digestion by a microsomal membrane fraction. In vivo studies were undertaken by transfecting into GH3 cells one of two expression vectors containing sequences that would produce either a full-length mRNA or a short (800-base) mRNA. The neomycin resistance gene was cotransfected with these plasmids, and 30 permanent cell lines were produced after selection in G418. Cell lines containing the full-length RNA secreted large quantities of ACTH and beta-endorphin immunoreactivity, whereas those expressing the short transcript secreted neither of these peptides. However extractable peptide was present in this latter type of cell line, thereby suggesting that the 800-base mRNA was translated, and that no peptide reached the secretory vesicle. These findings raise important questions about the role of peripheral POMC gene expression.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0888-8809
pubmed:author
pubmed:issnType
Print
pubmed:volume
4
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1737-43
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
In vitro and in vivo analysis of the processing and fate of the peptide products of the short proopiomelanocortin mRNA.
pubmed:affiliation
Department of Endocrinology, St. Bartholomew's Hospital Medical College, London, Great Britain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't