In individual T cells one productive alpha rearrangement does not appear to block rearrangement at the second allele.
The T cell lymphoma line BW5147 has rearranged TCR alpha chain genes segments on both the homologous chromosomes: one is functional (V alpha 1) and the second (V alpha 16.1) is a pseudogene. The extreme 3' position of the V alpha 16.1 gene segment in the V alpha locus allows us to recognize rearrangements of most V alpha gene segments using the V alpha 16 probe as a marker. The absence of the genomic V alpha 16.1 gene fragment in mature thymocytes, antigen-specific T cells, and in more than two-thirds of the peripheral T cells suggests that most T lymphocytes rearrange both alpha loci. It appears that productive alpha chain rearrangement on one allele probably does not block a subsequent rearrangement on the other alpha locus.
Kumar
V
V
Division of Biology, California Institute of Technology, Pasadena 91125.
Urban
J L
JL
Hood
L
L
D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D015332:Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor; D006801:Humans; D008969:Molecular Sequence Data; D013601:T-Lymphocytes / Q000276:immunology*