Linked Life Data

15388495

Source:http://linkedlifedata.com/resource/pubmed/id/15388495

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2005-1-7
pubmed:abstractText
In the brain, angiotensinogen (AGT) is primarily expressed in astrocytes; brain ANG II derived from locally produced AGT has been shown to influence blood pressure. To better understand the molecular basis of AGT expression in the brain, we identified a human astrocytoma cell line, CCF-STTG1, that expresses endogenous AGT mRNA and produces AGT protein. Studies examining CCF-STTG1 cell AGT after N- and O-glycosidase suggest that AGT may not be posttranslationally modified by glycosylation in these cells as it is in plasma. Small amounts of AGT (5% of HepG2) were detected in the culture medium, suggesting a low rate of AGT secretion. Immunocytochemical examination of AGT in CCF-STTG1 cells revealed mainly nuclear localization. Although this has not been previously reported, it is consistent with nuclear localization of other serpin family members. To examine this further, we generated a fusion protein consisting of green fluorescent protein (GFP) and human AGT and examined subcellular localization by confocal microscopy after confirming expression of the fusion protein by Western blot. In CCF-STTG1 cells, a control GFP construct lacking AGT was mainly localized in the cytoplasm, whereas the GFP-AGT fusion protein was primarily localized in the nucleus. To map the location of a potential nuclear localization signal, overlapping 500-bp fragments of human AGT cDNA were fused in frame downstream of GFP. Although four of the fusion proteins exhibited either perinuclear or cytoplasmic localization, one fusion protein encoding the COOH terminus of AGT was localized in the nucleus. Importantly, nuclear localization of human AGT was confirmed in primary cultures of glial cells isolated from transgenic mice expressing the human AGT under the control of its own endogenous promoter. Our results suggest that AGT may have a novel intracellular role in the brain apart from its predicted endocrine function.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0363-6119
pubmed:author
pubmed:issnType
Print
pubmed:volume
288
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
R539-46
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Nuclear localization of angiotensinogen in astrocytes.
pubmed:affiliation
Genetics Graduate Program, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't