Co-amplification of c-myc/pvt-1 in immortalized mouse B-lymphocytic cell lines results in a novel pvt-1/AJ-1 transcript.
In a series of mouse pvt-1 cDNA clones prepared from an immortalized B-cell line that contains an amplified c-myc/pvt-1 region, we have identified a unique cDNA, AJ-I, which contains 57 bp of pvt-1 sequence (pvt-1a) spliced to a novel sequence of 2.1 kb. We report here that this 3' segment (termed AJ-IX) maps more than 60 kb telomeric to pvt-1a and is encoded by a novel locus (AJ-I) on mouse chromosome 15. The AJ-IX probe detects a transcript that is expressed only in normal mouse brain and testis. Several mast-cell tumors, Ly-I+ B-lymphocytic cell lines and a neuroblastoma also display abundant levels of AJ-IX-specific mRNA. However, splicing of pvt-1a to AJ-IX is found exclusively in Ly-I+ B-cell lines that contain amplified c-myc/pvt-1. We conclude that some features in the generation of this amplicon facilitates the synthesis of a pvt-1/AJ-IX chimeric mRNA that may play a role in immortalization of these Ly-I+ B-cell lines.
Huppi
K
K
Molecular Genetics Section, NCI/NIH, Bethesda, MD 20892.
Siwarski
D
D
Shaughnessy
J D
JD
Mushinski
J F
JF
D000818:Animals; D001402:B-Lymphocytes / Q000502:physiology*; D001483:Base Sequence; D002460:Cell Line; D002874:Chromosome Mapping; D004247:DNA / Q000235:genetics; D015342:DNA Probes / Q000235:genetics*; D005784:Gene Amplification; D015870:Gene Expression; D016259:Genes, myc; D051379:Mice; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012333:RNA, Messenger / Q000235:genetics
D015342:DNA Probes; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D004247:DNA