title: The pre-B cell receptor and its role in proliferation and Ig heavy chain allelic exclusion.
abstract: The pre-B cell receptor (pre-BCR) is composed of the immunoglobulin (Ig) heavy (microH) chain and the surrogate light chain encoded by VpreB and lambda5. The pre-BCR has been implicated in precursor B cell proliferation, differentiation and IgH chain allelic exclusion. B cell development in mice lacking the transmembrane form of microH chain is blocked at the precursor B cell stage: the cells cannot proliferate or differentiate further and the IgH locus is allelically included. In mice lacking lambda5, the precursor B cells, although unable to proliferate, can nonetheless differentiate, whereas the IgH locus is allelically excluded. It was, therefore, postulated that microH chain together with VpreB could form a pre-BCR-like receptor that would allow IgH allelic exclusion but not proliferation. In mice lacking both VpreB genes, precursor B cells do not proliferate but are able to differentiate. Surprisingly, the IgH locus is allelically excluded. This suggests that microH chains find other partner proteins to signal allelic exclusion.
authors.affiliation: The Babraham Institute, Cambridge CB2 4AT, UK. lill.martensson@bbsrc.ac.uk
authors.forename: Inga-Lill
authors.initials: IL
authors.lastname: Mårtensson
authors.forename: Antonius
authors.initials: A
authors.lastname: Rolink
authors.forename: Fritz
authors.initials: F
authors.lastname: Melchers
authors.forename: Cornelia
authors.initials: C
authors.lastname: Mundt
authors.forename: Steve
authors.initials: S
authors.lastname: Licence
authors.forename: Takeyuki
authors.initials: T
authors.lastname: Shimizu
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology*; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology*; D002455:Cell Division / Q000235:genetics / Q000276:immunology; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D020868:Gene Silencing / Q000276:immunology; D007147:Immunoglobulin Light Chains; D054444:Immunoglobulin Light Chains, Surrogate; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000276:immunology*; D054420:Pre-B Cell Receptors; D011947:Receptors, Antigen, B-Cell
chemical_list: D007147:Immunoglobulin Light Chains; D054444:Immunoglobulin Light Chains, Surrogate; D008562:Membrane Glycoproteins; D054420:Pre-B Cell Receptors; D011947:Receptors, Antigen, B-Cell