Linked Life Data

1382088

Source:http://linkedlifedata.com/resource/pubmed/id/1382088

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1992-10-22
pubmed:abstractText
gp330, a large glycoprotein located in renal proximal tubules, has sequence similarities with the low-density lipoprotein receptor and the alpha 2-macroglobulin receptor/low-density lipoprotein receptor-related protein. The 40 KD human alpha 2-macroglobulin receptor-associated protein is a newly discovered heparin binding protein homologous to a major rat Heymann nephritis factor and exhibiting high affinity binding to the alpha 2-macroglobulin receptor. The present study shows by ligand blotting, light and electron microscopic autoradiography, and cytochemistry that gp330 located in coated apical membrane regions of the rat proximal tubule strongly binds the 40 KD protein. Furthermore, 45Ca2+ blotting experiments disclosed gp330 as a quantitatively important Ca2+ binding protein in renal cortex. Binding of 125I-labeled 40 KD protein to electroblotted gp330 and to coated apical membrane regions in sections of renal proximal tubules was abolished by excess unlabeled 40 KD protein, heparin, and EDTA. The endocytic properties of gp330 were investigated by in vivo microperfusion of rat proximal tubules. After 6 min, 125I-labeled 40 KD protein was mainly found in endocytic vacuoles and later accumulated in lysosomes. These data demonstrate that gp330 is a Ca2+ binding receptor for endocytosis of protein and is functionally related to the alpha 2-macroglobulin receptor/low-density lipoprotein receptor-related protein. Furthermore, our results demonstrate the usefulness of semi-thin and ultra-thin cryosections in studies of ligand binding and subcellular localization of receptors with autoradiographic techniques.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-1554
pubmed:author
pubmed:issnType
Print
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1481-90
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Renal tubule gp330 is a calcium binding receptor for endocytic uptake of protein.
pubmed:affiliation
Department of Cell Biology, University of Aarhus, Denmark.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't