Linked Life Data

8454858

Source:http://linkedlifedata.com/resource/pubmed/id/8454858

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1993-4-20
pubmed:abstractText
The predominant Ag-receptor complex of B cells consists of mIgM or mIgD noncovalently associated with glycosylated heterodimers of Ig-alpha and Ig-beta or Ig-alpha and Ig-gamma. Upon B cell stimulation the associated proteins are phosphorylated, giving rise to pp32/33 (alpha), pp37 (beta), and pp34 (previously designated gamma). Ig-alpha and Ig-beta contain extended cytoplasmic structure (61 and 48 amino acids, respectively) and associate with cytoplasmic effectors indicating that they are directly involved in signal transduction. Here we report analysis of the structural relationship of mIgM- and mIgD-associated Ig-beta and Ig-gamma chains from mice. N-terminal sequence, immunoblotting, and physicochemical analyses show that both Ig-beta and Ig-gamma are products of the B cell-specific B29 gene and demonstrate that the 37-kDa Ig-beta protein is the full length predicted product of the B29 gene. The Ig-associated protein that migrates in the 34-kDa range is actually two distinct species. The minor species is a phosphorylatable and underglycosylated form of full length Ig-beta, and the major species is a C-terminally truncated form of B29, which we now designate Ig-gamma. This conclusion is based on the observations that Ig-gamma is composed of a core protein which is 3 to 4 kDa smaller than deglycosylated Ig-beta, it is not phosphorylated, unlike Ig-beta, and it does not react with an antiserum raised against a peptide of the seven C-terminal amino acids of B29. Based on these findings we estimate that Ig-gamma is truncated by about 30 to 36 amino acid residues and hypothesize that the most 3' B29 exon, which encodes the 32 C-terminal residues, may not be expressed in Ig-gamma. All of the documented B29 products are found in association with both mIgM and mIgD. Interestingly, Ig-gamma is found in intermediate and low density splenic B cells, but is not detectable in resting B cells. This raises the possibility that it may confer some distinct signaling function on the Ag receptors of these cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
150
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2814-22
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:8454858-Amino Acid Sequence, pubmed-meshheading:8454858-Animals, pubmed-meshheading:8454858-Antigens, CD, pubmed-meshheading:8454858-Antigens, CD79, pubmed-meshheading:8454858-B-Lymphocyte Subsets, pubmed-meshheading:8454858-Cell Count, pubmed-meshheading:8454858-Cell Fractionation, pubmed-meshheading:8454858-Glycosylation, pubmed-meshheading:8454858-Immunoblotting, pubmed-meshheading:8454858-Immunoglobulin D, pubmed-meshheading:8454858-Immunoglobulin M, pubmed-meshheading:8454858-Membrane Glycoproteins, pubmed-meshheading:8454858-Mice, pubmed-meshheading:8454858-Mice, Inbred BALB C, pubmed-meshheading:8454858-Mice, Inbred C57BL, pubmed-meshheading:8454858-Molecular Sequence Data, pubmed-meshheading:8454858-Molecular Weight, pubmed-meshheading:8454858-Phosphoproteins, pubmed-meshheading:8454858-Phosphorylation, pubmed-meshheading:8454858-Precipitin Tests, pubmed-meshheading:8454858-Receptors, Antigen, B-Cell, pubmed-meshheading:8454858-Spleen
pubmed:year
1993
pubmed:articleTitle
The gamma subunit of the B cell antigen-receptor complex is a C-terminally truncated product of the B29 gene.
pubmed:affiliation
National Jewish Center for Immunology and Respiratory Medicine, Department of Pediatrics, Denver, CO 80206.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.