Isolation of early immunoglobulin lambda-like gene transcripts in human fetal liver

Eur J Immunol. 1989 Oct;19(10):1873-8. doi: 10.1002/eji.1830191018.

Abstract

In an attempt to identify early events of human Ig gene expression, we have screened a human fetal liver cDNA library (less than 90 days of gestation) with C mu-, C gamma-, C kappa-, C lambda-specific probes and we report the characterization of two clones, F lambda 1 and F lambda 8, that hybridized with a human C lambda gene. These two clones, which are only 85% homologous to the functional C lambda genes, were shown to be additional nonallelic members of the 14.1/16.1 C lambda-like family. Using pulsed field gel electrophoresis these three C lambda-like genes were shown to be present on a 200-kb DNA fragment, defining a cluster distinct from that of the C lambda one. F lambda 1 and F lambda 8 contained an identical C lambda-like region, and differed from each other by a splicing event which joins a J lambda-like to the C lambda-like exon in the F lambda 1 clone in the absence of any rearrangement. Homologies observed between F lambda 1 and the mouse lambda 5 gene suggest that this human clone may contain the exon 2 and 3 equivalents of lambda 5. Since lambda 5 is selectively expressed in pre-B cells, our proposal is also supported by the early expression of this clone, together with the presence of full-length mu and gamma transcripts and the absence of functional Ig light chain transcripts. The presence of one nucleotide deletion in the C region of F lambda 1 conferring it a pseudogene status, the actual lambda 5 equivalent might be either one of the 14.1 or 16.1 human C lambda-like genes, the function of which is so far unknown.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA / analysis
  • Electrophoresis
  • Exons
  • Fetus / immunology*
  • Gene Rearrangement
  • Genes, Immunoglobulin*
  • HLA-DR Antigens / genetics
  • Humans
  • Immunoglobulin lambda-Chains / genetics*
  • Liver / immunology*
  • Molecular Weight
  • Sequence Homology, Nucleic Acid
  • Transcription, Genetic*

Substances

  • HLA-DR Antigens
  • Immunoglobulin lambda-Chains
  • DNA