Mouse bcl-3: cDNA structure, mapping and stage-dependent expression in B lymphocytes.
Human B-cell chronic lymphocytic leukemias (CLLs) are malignancies of mature B lymphocytes. A subset of these tumors is associated with a non-random t(14; 19) translocation (Ueshima et al., 1985). Recently a gene (bcl-3) has been identified in the region adjacent to the chromosome 19 breakpoint in this translocation (McKeithan et al., 1987; Ohno et al., 1990). We now report the isolation of cDNA clones of mouse bcl-3. The mouse bcl-3-coding region is 1746 bp long and exhibits 80% identity with human bcl-3 at both the nucleotide and amino acid level. The bcl-3 locus maps to the proximal end of mouse chromosome 7, which is syntenic to human chromosome 19. The bcl-3 probe readily detects particularly abundant amounts of a 1.8 kb mRNA in mouse tumors consisting of follicular center mature B cells and large pre-B cells, but not in small pre-B cells. The bcl-3 pattern of expression is distinctive in the spectrum of B-cell maturation in that bcl-3 transcripts are particularly abundant in B-cell lines immortalized just prior to Ig switch. The bcl-3 pattern of expression also bears close resemblance to that of bcl-2 (Gurfinkel et al., 1987), which is frequently associated with human B follicular lymphomas [t(14; 18)] and some chronic lymphocytic leukemias (Adachi et al., 1989; 1990; Adachi & Tsujimoto, 1989).
Bhatia
K
K
Pediatrics Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892.
Huppi
K
K
McKeithan
T
T
Siwarski
D
D
Mushinski
J F
JF
Magrath
I
I
D000595:Amino Acid Sequence; D000818:Animals; D000081242:B-Cell Lymphoma 3 Protein; D001402:B-Lymphocytes / Q000502:physiology*; D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D015870:Gene Expression; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics; D051379:Mice; D008969:Molecular Sequence Data; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D011519:Proto-Oncogenes; D012091:Repetitive Sequences, Nucleic Acid; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors
D000081242:B-Cell Lymphoma 3 Protein; C000631344:BCL3 protein, human; C000631345:Bcl3 protein, mouse; D011518:Proto-Oncogene Proteins; D014157:Transcription Factors; D004247:DNA