Molecular analysis of the chromosomal breakpoint and fusion transcripts in the acute lymphoblastic SEM cell line with chromosomal translocation t(4;11).
The chromosomal breakpoint and fusion transcripts of the pre-B-leukaemia-derived SEM cell line carrying a reciprocal t(4;11)(q21;q23) translocation were analysed. The breakpoint from derivative chromosome der4 was cloned and sequenced. The crossover site was localized in intron 7 of the ALL-1 gene on chromosome 11q23 and in a large intron of the AF-4 (FEL) gene. RNA transcripts from both wild-type genes and both hybrid genes were detected by reverse transcriptase polymerase chain reaction (RT-PCR) assays. In addition, alternatively spliced mRNA species derived from the der4 chromosome were found. They were generated by using the exon 5' of the breakpoint on der4 as a common splice donor site and the 5' boundaries of exons 8 or 9 of the ALL-1 gene as alternative splice acceptor sites. The hypothesis is proposed that selective pressure operators to maintain the presence of both derivative chromosomes as important elements in the leukaemogenic process.
Marschalek
R
R
Department of Genetics, University of Erlangen-Nürnberg, Germany.
Greil
J
J
Löchner
K
K
Nilson
I
I
Siegler
G
G
Zweckbronner
I
I
Beck
J D
JD
Fey
G H
GH
D001483:Base Sequence; D015139:Blotting, Southern; D002675:Child, Preschool; D002874:Chromosome Mapping; D002880:Chromosomes, Human, Pair 11; D002894:Chromosomes, Human, Pair 4; D005260:Female; D006801:Humans; D008969:Molecular Sequence Data; D015514:Oncogene Proteins, Fusion / Q000096:biosynthesis*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics*; D014178:Translocation, Genetic; D014407:Tumor Cells, Cultured
D015514:Oncogene Proteins, Fusion