Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
48
pubmed:dateCreated
2010-11-24
pubmed:abstractText
The low affinity receptor for IgE, CD23, is the natural regulator of IgE synthesis, and understanding both the synthesis and the catabolism of CD23 are, thus, important issues. Membrane CD23 is cleaved by a disintegrin and metalloproteinase 10 (ADAM10) and this cleavage influences the ability of CD23 to regulate IgE. In contrast to the belief that cleavage is a cell surface event, endosomal neutralization with NH(4)Cl was found to dramatically reduce CD23 cleavage, suggesting that the majority of CD23 cleavage occurred subsequent to internalization in the endosomal pathway and not at the cell surface. In line with this, full-length CD23 was shown to be sorted in an ADAM10-dependent manner into exosomes. Greatly increased ADAM10-mediated CD23 cleavage was seen at endosomal pH. Additionally, the stalk region of CD23 was found to interact with ADAM10 and ADAM10 binding of CD23 was found to be protease independent. SPR analysis of the interaction indicated about a 10-fold increase in the R(max) at endosomal pH (pH 5.8) compared with pH 7.4, whereas the affinity of the interaction was not significantly changed. The R(max) change, combined with the increased cleavage at endosomal pH, indicates greater accessibility of the CD23 stalk region for ADAM10 at the lower pH. These results indicate a model where CD23 internalization results in ADAM10-dependent incorporation into exosomes, followed by partial cleavage of CD23 by ADAM10 prior to being released from the cell. The increased cleavage at endosomal pH also has implications for other ADAM10 substrates.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1083-351X
pubmed:author
pubmed:issnType
Electronic
pubmed:day
26
pubmed:volume
285
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
37531-41
pubmed:dateRevised
2011-1-6
pubmed:meshHeading
pubmed-meshheading:20876574-ADAM Proteins, pubmed-meshheading:20876574-Amyloid Precursor Protein Secretases, pubmed-meshheading:20876574-Animals, pubmed-meshheading:20876574-B-Lymphocytes, pubmed-meshheading:20876574-Cell Line, pubmed-meshheading:20876574-Cells, Cultured, pubmed-meshheading:20876574-Exosomes, pubmed-meshheading:20876574-Humans, pubmed-meshheading:20876574-Hydrogen-Ion Concentration, pubmed-meshheading:20876574-Kinetics, pubmed-meshheading:20876574-Membrane Proteins, pubmed-meshheading:20876574-Mice, pubmed-meshheading:20876574-Mice, Inbred C57BL, pubmed-meshheading:20876574-Mice, Knockout, pubmed-meshheading:20876574-Protein Binding, pubmed-meshheading:20876574-Protein Processing, Post-Translational, pubmed-meshheading:20876574-Protein Transport, pubmed-meshheading:20876574-Receptors, IgE
pubmed:year
2010
pubmed:articleTitle
CD23 Sheddase A disintegrin and metalloproteinase 10 (ADAM10) is also required for CD23 sorting into B cell-derived exosomes.
pubmed:affiliation
Department of Microbiology and Immunology, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural