Affordable Access

Burkitt lymphoma cell line carrying a variant translocation creates new DNA at the breakpoint and violates the hierarchy of immunoglobulin gene rearrangement.

Authors
Publication Date
Source
PMC
Keywords
License
Unknown

Abstract

The Burkitt lymphoma cell line KK124, which contains a reciprocal t(8;22) translocation, was shown to have rearranged in a region 3' to the c-myc proto-oncogene on chromosome 8 and 5' to the lambda constant region on chromosome 22. The breakpoint was cloned and sequenced, revealing that c-myc and a portion of its 3' region abutted a complete lambda variable gene that had undergone V-J recombination. Since this cell line expresses kappa light chain, this lambda rearrangement violates the previously proposed hierarchy of immunoglobulin gene rearrangement. A novel duplication of normal chromosome 8 sequences was also found at the breakpoint. The first exon of c-myc and its flanking sequence from the translocated allele was sequenced and compared with a normal counterpart. Extensive mutation was found within the first exon in contrast to its 3' and 5' flanking regions. S1 nuclease analysis revealed that it was the translocated c-myc being expressed and that there was a promoter shift from P2 to P1. The detailed structural analysis of this cell line provides clues concerning mechanisms of chromosomal translocation and c-myc deregulation in Burkitt lymphomas.

Statistics

Seen <100 times