Expression and cellular localization of dbpC/Contrin in germ cell tumor cell lines.
The transcriptional regulation of the germ cell-specific cold-shock domain protein dbpC/Contrin was investigated, and the promoter region between -272 and -253 relative to the transcription start site was shown to be critical for the manifestation of cell-type specific transcription. In vivo footprint analysis demonstrated that the E-box located between -272 and -253 is protected in the dbpC/Contrin-positive germ cell tumor cell lines NEC8 and TERA1, but not in the dbpC/Contrin-negative bladder cancer cell line T24 or ovarian cancer cell line A2780. The promoter activity of the dbpC/Contrin gene was transactivated by co-transfection with c-Myc and the N-Myc expression plasmid. Western blotting analysis clearly showed that N-Myc is highly expressed in both NEC8 and TERA1 cells, and that c-Myc is expressed in both T24 and A2780 cells. These data demonstrate that cell-type specific dbpC/Contrin expression in germ cells is regulated by N-Myc. In addition, dbpC/Contrin is localized mainly in the cytoplasm of NEC8 and TERA1 cells, but is translocated to the nucleus when its C-terminal region is partially deleted. Our findings also suggest that dbpC/Contrin can be used as a molecular tool for the detection of germ cell tumors.
Yoshida
Takeshi
T
Department of Molecular Biology, University of Occupational and Environmental Health School of Medicine, Iseigaoka, Kitakyushu 807-8555, Japan.
Izumi
Hiroto
H
Uchiumi
Takeshi
T
Sasaguri
Yasuyuki
Y
Tanimoto
Akihide
A
Matsumoto
Tetsuro
T
Naito
Seiji
S
Kohno
Kimitoshi
K
D021581:Active Transport, Cell Nucleus; D000595:Amino Acid Sequence; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D009373:Neoplasms, Germ Cell and Embryonal / Q000473:pathology*; D011401:Promoter Regions, Genetic; D016271:Proto-Oncogene Proteins c-myc / Q000502:physiology; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation
C489427:MYC protein, human; D016271:Proto-Oncogene Proteins c-myc; D016601:RNA-Binding Proteins; C485481:YBX2 protein, human