Assembly of the truncated immunoglobulin heavy chain D mu into antigen receptor-like complexes in pre-B cells but not in B cells.
Rearrangements of the IgH locus with JH joined to reading frame 2 of DH are greatly underrepresented in B cells. These rearrangements encode the truncated heavy chain D mu. In pre-B cells, we found D mu protein expressed on the cell surface and assembled into a complex with surrogate light chains, Ig alpha, and Ig beta. Cross-linking of either mu m- or D mu m- containing pre-B cell receptors triggered signal transduction reactions. In contrast, when expressed in mature B cell lines, D mu was not detected on the cell surface and did not efficiently bind kappa immunoglobulin light chains, but did associate with Ig alpha and Ig beta. These results characterize the interactions of D mu chain with other components of the B cell antigen receptor complex and suggest possible mechanisms by which D mu expression may interfere with B cell development.
Horne
M C
MC
Department of Microbiology, University of California, San Francisco 94143-0552, USA.
Roth
P E
PE
DeFranco
A L
AL
D000818:Animals; D016175:B-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D002461:Cell Line, Transformed; D015322:Gene Rearrangement, B-Lymphocyte / Q000276:immunology*; D005803:Genes, Immunoglobulin / Q000276:immunology*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D007143:Immunoglobulin Heavy Chains / Q000235:genetics* / Q000378:metabolism; D007147:Immunoglobulin Light Chains / Q000235:genetics; D054444:Immunoglobulin Light Chains, Surrogate; D007075:Immunoglobulin M / Q000235:genetics* / Q000378:metabolism; D007135:Immunoglobulin Variable Region / Q000235:genetics* / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000235:genetics; D051379:Mice; D011947:Receptors, Antigen, B-Cell / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology
D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D054444:Immunoglobulin Light Chains, Surrogate; D007075:Immunoglobulin M; D007135:Immunoglobulin Variable Region; D008562:Membrane Glycoproteins; D011947:Receptors, Antigen, B-Cell