Transposition of the immunoglobulin heavy chain enhancer to the myc oncogene in a murine plasmacytoma

Abstract

A novel mechanism of oncogene activation by transposition of a tissue-specific cellular enhancer is described. A rearranged c-myc oncogene was cloned from murine plasmacytoma ABPC17 in the expectation that it would reflect the t(6;15) chromosome translocation carried by this tumor. The rearrangement instead reflects an insertion 361 bp 5′ to the c-myc gene on chromosome 15. The insert conveys a 2.3 kb segment of the immunoglobulin heavy (H) chain locus from chromosome 12. Since the insertion introduces the lymphoid-specific enhancer from the JH-Sμ region and also disrupts a region implicated in normal c-myc control, it may account for the c-myc transcription observed in ABPC17. The structure..