Targeted disruption of mu chain membrane exon causes loss of heavy-chain allelic exclusion

Nature. 1992 Mar 12;356(6365):154-6. doi: 10.1038/356154a0.


Burnet's clonal selection theory suggests that each B lymphocyte is committed to a single antibody specificity. This is achieved by a programme of somatic rearrangements of the gene segments encoding antibody variable (V) regions, in the course of B-cell development. Evidence from immunoglobulin-transgenic mice and immunoglobulin-gene-transfected transformed pre-B cells suggest that the membrane form of the immunoglobulin heavy (H) chain of class mu (microns), expressed from a rearranged H-chain (IgH) locus, may signal allelic exclusion of the homologous IgH locus in the cell and initiation of light (L)-chain gene rearrangement in the Ig kappa loci. We report here that targeted disruption of the membrane exon of the mu chain indeed results in the loss of H-chain allelic exclusion. But, some kappa chain gene rearrangement is still observed in the absence of micron expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles*
  • Animals
  • B-Lymphocytes / immunology*
  • Base Sequence
  • Bone Marrow Cells
  • DNA / chemistry
  • Exons*
  • Gene Rearrangement, B-Lymphocyte, Heavy Chain
  • Gene Rearrangement, B-Lymphocyte, Light Chain
  • Genes, Immunoglobulin*
  • Immunoglobulin kappa-Chains / genetics
  • Immunoglobulin mu-Chains / genetics*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Molecular Sequence Data
  • Mutation
  • Polymerase Chain Reaction
  • Spleen / cytology


  • Immunoglobulin kappa-Chains
  • Immunoglobulin mu-Chains
  • DNA