Biomaterial Database

B29: a member of the immunoglobulin gene superfamily exclusively expressed on beta-lineage cells. 1988

G G Hermanson, and D Eisenberg, and P W Kincade, and R Wall

Molecular Biology Institute, University of California, Los Angeles 90024.

A number of the glycoproteins identified on the surfaces of cells of the immune response belong to the immunoglobulin superfamily. We have isolated and characterized cDNA clones and the complete genomic gene encoding a B-cell-specific member of the immunoglobulin superfamily called "B29." This isolate is expressed at all stages in B-cell development beginning with the earliest precursor B cells undergoing immunoglobulin heavy chain gene diversity region----joining region gene (DH----JH) rearrangements. The protein sequence predicted by the B29 coding region contains a leader sequence and a single extracellular immunoglobulin-like domain, followed by a hydrophobic transmembrane segment and a charged intracytoplasmic domain. The immunoglobulin-like domain contains cysteines and other conserved amino acids characteristic of light chain variable and joining regions, but overall the sequence is only distantly related to immunoglobulins. Each of these domains is encoded in separate exons in the B29 gene, in analogy to other members of the immunoglobulin superfamily. The conserved structural features of the immunoglobulin-like domain in the B29 gene product resemble those of other members of the immunoglobulin superfamily involved in cell recognition and adhesion.

UI	MeSH Term	Description	Entries
D007136	Immunoglobulins	Multi-subunit proteins which function in IMMUNITY. They are produced by B LYMPHOCYTES from the IMMUNOGLOBULIN GENES. They are comprised of two heavy (IMMUNOGLOBULIN HEAVY CHAINS) and two light chains (IMMUNOGLOBULIN LIGHT CHAINS) with additional ancillary polypeptide chains depending on their isoforms. The variety of isoforms include monomeric or polymeric forms, and transmembrane forms (B-CELL ANTIGEN RECEPTORS) or secreted forms (ANTIBODIES). They are divided by the amino acid sequence of their heavy chains into five classes (IMMUNOGLOBULIN A; IMMUNOGLOBULIN D; IMMUNOGLOBULIN E; IMMUNOGLOBULIN G; IMMUNOGLOBULIN M) and various subclasses.	Globulins, Immune,Immune Globulin,Immune Globulins,Immunoglobulin,Globulin, Immune
D007143	Immunoglobulin Heavy Chains	The largest of polypeptide chains comprising immunoglobulins. They contain 450 to 600 amino acid residues per chain, and have molecular weights of 51-72 kDa.	Immunoglobulins, Heavy-Chain,Heavy-Chain Immunoglobulins,Ig Heavy Chains,Immunoglobulin Heavy Chain,Immunoglobulin Heavy Chain Subgroup VH-I,Immunoglobulin Heavy Chain Subgroup VH-III,Heavy Chain Immunoglobulins,Heavy Chain, Immunoglobulin,Heavy Chains, Ig,Heavy Chains, Immunoglobulin,Immunoglobulin Heavy Chain Subgroup VH I,Immunoglobulin Heavy Chain Subgroup VH III,Immunoglobulins, Heavy Chain
D007144	Immunoglobulin J-Chains	A 15 kDa "joining" peptide that forms one of the linkages between monomers of IMMUNOGLOBULIN A or IMMUNOGLOBULIN M in the formation of polymeric immunoglobulins. There is one J chain per one IgA dimer or one IgM pentamer. It is also involved in binding the polymeric immunoglobulins to POLYMERIC IMMUNOGLOBULIN RECEPTOR which is necessary for their transcytosis to the lumen. It is distinguished from the IMMUNOGLOBULIN JOINING REGION which is part of the IMMUNOGLOBULIN VARIABLE REGION of the immunoglobulin light and heavy chains.	Ig J Chains,J-Chains, Immunoglobulin,Ig J-Peptide,Immunoglobulin J Polypeptide,Immunoglobulin J-Peptide,Chains, Ig J,Ig J Peptide,Immunoglobulin J Chains,Immunoglobulin J Peptide,J Chains, Ig,J Chains, Immunoglobulin,J Polypeptide, Immunoglobulin,J-Peptide, Ig,J-Peptide, Immunoglobulin,Polypeptide, Immunoglobulin J
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D003001	Cloning, Molecular	The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.	Molecular Cloning
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D000917	Antibody Formation	The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.	Antibody Production,Antibody Response,Antibody Responses,Formation, Antibody,Production, Antibody,Response, Antibody,Responses, Antibody