Linked Life Data

7673354

Source:http://linkedlifedata.com/resource/pubmed/id/7673354

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1995-10-19
pubmed:abstractText
Maternal IgG crosses the proximal small intestine of the suckling rat by receptor-mediated endocytosis and transepithelial transport. The Fc receptor resembles the major histocompatibility complex class I antigens in that it consists of two subunits: a transmembrane glycoprotein (gp50) in association with beta 2-microglobulin. We used immunofluorescence microscopy and quantitative immunogold cytochemistry to study the subcellular distribution of the two subunits. In mature absorptive cells both subunits were colocalized in each of the membrane compartments that mediate transcytosis of IgG. IgG administered in situ apparently caused both subunits to concentrate within endocytic pits of the apical plasma membrane, suggesting that ligand causes redistribution of receptors at this site. These results support a model for transport in which IgG is transferred across the cell as a complex with both subunits. During absorptive cell differentiation, gp50 and beta 2-microglobulin showed nearly identical patterns of increased expression that accompanied the development of the apical endocytic apparatus and terminal web. However, absorptive cells in weanling rats expressed no detectable gp50 and only low levels of beta 2-microglobulin in the Golgi region and on the basolateral plasma membrane where class I antigens would likely reside. Thus, beta 2-microglobulin has a novel distribution unrelated to its function as a subunit of the class I antigens. The co-expression of the two receptor subunits is restricted to neonatal epithelial cells engaged in IgG transport and is coordinately regulated during absorptive cell differentiation and during postnatal intestinal development.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9533
pubmed:author
pubmed:issnType
Print
pubmed:volume
108 ( Pt 6)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2347-60
pubmed:dateRevised
2005-11-17
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Beta 2-microglobulin co-distributes with the heavy chain of the intestinal IgG-Fc receptor throughout the transepithelial transport pathway of the neonatal rat.
pubmed:affiliation
Department of Biology, University of Virginia, Charlottesville 22901, USA.
pubmed:publicationType
Journal Article