Tissue-specific expression of mRNA in mouse lymphocytes detected by v-fos but not by human c-fos DNA probes.
Transcription of the c-fos gene is known to be induced transiently by many types of cellular stimuli in various cultured cell lines; however, several authors have reported that the c-fos gene is constitutively transcribed in lymphoid cells. We detected, in fact, abundant transcripts which hybridized with a v-fos DNA probe in nuclear run-off transcripts and poly(A)+ RNA of both quiescent mouse splenic lymphocytes and unstimulated monocytic tumor cell lines. However, human c-fos cDNA did not hybridize with most of these transcripts. No signal was detected by v-fos probe in nuclear run-off transcripts of 3T3 fibroblasts, and c-fos was inducible in both the 3T3 cells and the monocytic tumor cell lines. In quiescent lymphocytes, only the 0.3 kb HincII-PvuII portion of v-fos DNA, which contains a repeat of CAAAA, hybridized with these transcripts; neither other parts of v-fos nor human c-fos DNAs did. These results suggest that a significant portion of the previously reported 'constitutive' transcripts detected by v-fos DNA in lymphocytes and monocytes are not transcripts of c-fos but of other sequences which are specifically expressed in lymphoid cells and have homology with the 0.3 kb HincII-PvuII fragment of v-fos.
Kikuchi
K
K
Department of Chemical Engineering, Faculty of Engineering, University of Tokyo, Japan.
Makishima
F
F
D000818:Animals; D015152:Blotting, Northern; D002478:Cells, Cultured; D015342:DNA Probes; D005347:Fibroblasts / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D008813:Mice, Inbred ICR; D009000:Monocytes / Q000378:metabolism; D016761:Oncogene Proteins v-fos; D009856:Oncogene Proteins, Viral / Q000235:genetics*; D009928:Organ Specificity; D011061:Poly A / Q000032:analysis*; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics*; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger / Q000032:analysis*; D012334:RNA, Neoplasm / Q000032:analysis; D012091:Repetitive Sequences, Nucleic Acid; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured / Q000378:metabolism
D015342:DNA Probes; D016761:Oncogene Proteins v-fos; D009856:Oncogene Proteins, Viral; D011518:Proto-Oncogene Proteins; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D011061:Poly A