Two antisense promoters in the immunoglobulin mu-switch region drive expression of c-myc in the Burkitt's lymphoma cell line BL67.
In the Burkitt's lymphoma (BL) cell line BL67 the first exon of the c-myc gene is fused to the mu-switch region of the immunoglobulin heavy-chain gene (IgH). BL67 cells express IgH/c-myc hybrid RNAs which are initiated in the immunoglobulin locus, transcribed across the chromosomal breakpoint into the first exon of c-myc and spliced using the physiological splice donor and acceptor sites of the c-myc gene. We have isolated cDNAs of these hybrid RNAs and characterized the start points in the Ig heavy-chain gene. Two promoters were identified in the mu-switch region of BL67 cells which give rise to antisense transcription of the mu-gene. These promoters are also active in other BL cell lines, in B cells without Ig translocation and in a T-cell line. Both promoters co-localize with DNAase I-hypersensitive sites, HNF and HSW, in the mu-switch region. The structures of IgH/c-myc hybrid RNAs and of the corresponding promoters are described.
Apel
T W
TW
Institut für Klinische Molekularbiologie und Tumorgenetik, Forschungszentrum für Umwelt and Gesundheit, GSF, München-Grosshadern, Germany.
Mautner
J
J
Polack
A
A
Bornkamm
G W
GW
Eick
D
D
D001483:Base Sequence; D002051:Burkitt Lymphoma / Q000235:genetics*; D003001:Cloning, Molecular; D016373:DNA, Antisense / Q000502:physiology*; D003850:Deoxyribonuclease I; D005091:Exons; D015870:Gene Expression / Q000235:genetics; D015723:Gene Library; D016259:Genes, myc / Q000235:genetics*; D006801:Humans; D007134:Immunoglobulin Switch Region / Q000235:genetics*; D007148:Immunoglobulin mu-Chains / Q000235:genetics*; D007438:Introns; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D015719:Single-Strand Specific DNA and RNA Endonucleases; D014178:Translocation, Genetic / Q000235:genetics; D014407:Tumor Cells, Cultured
D016373:DNA, Antisense; D007148:Immunoglobulin mu-Chains; D003850:Deoxyribonuclease I; D015719:Single-Strand Specific DNA and RNA Endonucleases