Linked Life Data

1890988

Source:http://linkedlifedata.com/resource/pubmed/id/1890988

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1991-10-16
pubmed:abstractText
AtT20 (pituitary corticotroph) cells were transfected with either the native or a mutant [AspB10]rat insulin II gene, using a plasmid containing the insulin gene and a neomycin resistance gene under the control of independent constitutive promoters. The cellular immunoreactive insulin (IRI) content ranged from 0.8-440 ng/10(6) cells, with the highest value similar to that found for a rat insulinoma cell line (RIN) and corresponding to approximately 1% that of native pancreatic B-cells. There was a direct correlation between insulin mRNA levels and IRI content and no correlation between mRNA levels and rat insulin II gene copy number. Furthermore, in some lines the insulin II transgene was lost even though the gene encoding neomycin resistance was retained. IRI release was stimulated up to 4-fold by isobutylmethylxanthine in all lines transfected with the native rat insulin II gene, and HPLC analysis showed most IRI as fully processed insulin, with less than 5% as proinsulin. These cells, thus, directed most proinsulin to secretory granules for conversion and regulated release regardless of the absolute amount of IRI expressed. One of the lines transfected with the AspB10 mutant gene (line AA9) released nearly 50% of IRI as proinsulin under basal conditions, with stimulation of insulin, but not proinsulin, release by isobutylmethylxanthine. This confirmed our previous finding of partial diversion of this mutant proinsulin from the regulated to the constitutive pathway. A second line (IC6) expressing the same mutant gene at much higher levels appeared to direct all mutant proinsulin to the regulated pathway, suggesting that for this particular mutant proinsulin, the secretory pathway employed by the transfected cells can be affected by the amount of proinsulin synthesized.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0888-8809
pubmed:author
pubmed:issnType
Print
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
319-26
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Heterogeneity of expression and secretion of native and mutant [AspB10]insulin in AtT20 cells.
pubmed:affiliation
Elliott P. Joslin Research Laboratory, Joslin Diabetes Center, Boston, Massachusetts.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't