Effects of translocations on transcription from PVT.
We have previously described a transcription unit on human chromosome 8, designated as PVT, that is consistently disrupted by the minority forms of translocations [t(2;8) and t(8;22)] in Burkitt's lymphoma. PVT begins 57 kilobase pairs downstream of the proto-oncogene MYC and is more than 200 kilobase pairs in length. In order to explore the pathogenic impact of translocations affecting PVT, we have characterized further the structure and transcription of the locus. In normal cells, PVT is transcribed into a variety of RNAs, the diversity of which remains unexplained. Alleles of PVT affected by translocations give rise to additional RNAs. These RNAs arise from a fusion of the first exon of PVT on chromosome 8 to the constant region of an immunoglobulin light chain on either chromosome 2 or chromosome 22. We have found no evidence that any of the normal or abnormal transcripts of PVT give rise to a protein. Our results suggest that the pathogenic effects of the variant translocations in Burkitt's lymphoma are not executed by a gene situated in a vicinity of the chromosomal breakpoints. Instead, our data leave open the possibility that the effects of the translocations may be mediated by activation of the relatively distant MYC gene.
Shtivelman
E
E
G. W. Hooper Research Foundation, Department of Microbiology and Immunology, University of California Medical Center, San Francisco 94143.
Bishop
J M
JM
D001483:Base Sequence; D002051:Burkitt Lymphoma / Q000235:genetics*; D002874:Chromosome Mapping; D002892:Chromosomes, Human, Pair 22; D002898:Chromosomes, Human, Pair 8; D003001:Cloning, Molecular; D015723:Gene Library; D014644:Genetic Variation; D006801:Humans; D008969:Molecular Sequence Data; D011505:Protein-Tyrosine Kinases / Q000235:genetics; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins / Q000235:genetics; D016271:Proto-Oncogene Proteins c-myc; D011519:Proto-Oncogenes; D012334:RNA, Neoplasm / Q000235:genetics; D014158:Transcription, Genetic; D014178:Translocation, Genetic
C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins; D016271:Proto-Oncogene Proteins c-myc; D012334:RNA, Neoplasm; D011505:Protein-Tyrosine Kinases