Nonequivalent nuclear location of immunoglobulin alleles in B lymphocytes.
Individual B lymphocytes normally express immunoglobulin (Ig) proteins derived from single Ig heavy chain (H) and light chain (L) alleles. Allelic exclusion ensures monoallelic expression of Ig genes by each B cell to maintain single receptor specificity. Here we provide evidence that at later stages of B cell development, additional mechanisms may contribute to prioritizing expression of single IgH and IgL alleles. Fluorescent in situ hybridization analysis of primary splenic B cells isolated from normal and genetically manipulated mice showed that endogenous IgH, kappa and lambda alleles localized to different subnuclear environments after activation and had differential expression patterns. However, this differential recruitment and expression of Ig alleles was not typically seen among transformed B cell lines. These data raise the possibility that epigenetic factors help maintain the monoallelic expression of Ig.
Skok
J A
JA
Lymphocyte Development Group, MRC Clinical Sciences Centre, Imperial College School of Medicine, Hammersmith Hospital, Du Cane Road, London W12 ONN, UK.
Brown
K E
KE
Azuara
V
V
Caparros
M L
ML
Baxter
J
J
Takacs
K
K
Dillon
N
N
Gray
D
D
Perry
R P
RP
Merkenschlager
M
M
Fisher
A G
AG
D000483:Alleles; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002461:Cell Line, Transformed; D002467:Cell Nucleus / Q000235:genetics*; D002478:Cells, Cultured; D002503:Centromere / Q000737:chemistry; D002999:Clone Cells; D015322:Gene Rearrangement, B-Lymphocyte; D005803:Genes, Immunoglobulin; D007143:Immunoglobulin Heavy Chains / Q000096:biosynthesis / Q000235:genetics*; D007147:Immunoglobulin Light Chains / Q000096:biosynthesis / Q000235:genetics*; D007145:Immunoglobulin kappa-Chains / Q000096:biosynthesis / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D008213:Lymphocyte Activation; D051379:Mice; D012333:RNA, Messenger / Q000096:biosynthesis; D013154:Spleen / Q000276:immunology
D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D007145:Immunoglobulin kappa-Chains; D012333:RNA, Messenger