Deregulated c-myc expression in quiescent CHO cells induces target gene transcription and subsequent apoptotic phenotype.
Human c-myc cDNA was fused with the hormone-binding domain (HBD) cDNA of murine estrogen receptor gene and the chimeric gene was introduced into the CHO cells. The fusion protein, c-MycER, becomes activated when the synthetic steroid, 4-hydroxy-tamoxifen (OHT), binds HBD. Activated c-MycER, likely c-Myc, can induce quiescent CHO cells reentry into S phase and subsequent cell death under serum-free condition. In addition, the expression of some proposed c-myc target genes such as ODC, MrDb, cad, rcc1 and rcl were found to increase upon OHT induction before S phase entry and apoptosis, indicating that these target genes are involved in cell cycle regulation and/or apoptosis control. However, the mutant D106-143c-MycER protein does not have above activities.
Fang
C M
CM
Laboratory of Molecular and Cellular Oncology, Shanghai Institute of Cell Biology, Chinese Academy of Sciences.
Shi
C
C
Xu
Y H
YH
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D016466:CHO Cells / Q000378:metabolism; D006224:Cricetinae; D020847:Estrogen Receptor Modulators / Q000494:pharmacology; D005786:Gene Expression Regulation; D010641:Phenotype; D016271:Proto-Oncogene Proteins c-myc / Q000096:biosynthesis* / Q000235:genetics; D011960:Receptors, Estrogen / Q000819:agonists / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics; D013629:Tamoxifen / Q000031:analogs & derivatives / Q000494:pharmacology; D014158:Transcription, Genetic
D020847:Estrogen Receptor Modulators; D016271:Proto-Oncogene Proteins c-myc; D011960:Receptors, Estrogen; D011993:Recombinant Fusion Proteins; D013629:Tamoxifen; C016601:afimoxifene