Article

Genomic instability in MycER-activated Rat1A-MycER cells.

Manitoba Institute of Cell Biology, Winnipeg, Canada.
Chromosome Research (impact factor: 3.09). 09/1996; 4(5):365-71. DOI:10.1007/BF02257272 pp.365-71
Source: PubMed

ABSTRACT The deregulated expression of c-Myc protein is associated with the non-random locus-specific amplification of the dihydrofolate reductase (DHFR) gene. This study was performed to determine whether additional chromosomal aberrations occur when c-Myc protein levels are up-regulated for prolonged periods. To this end, we have used Rat1A-MycER cells, which allow the experimental regulation of Myc protein levels. We examined the genomic stability of Rat1A-MycER cells cultivated in either the absence or the presence of estrogen, which reportedly activates the chimeric MycER protein in these cells. Following prolonged periods of MycER activation, Rat1A-Mycer cells exhibited irreversible chromosomal aberrations. The aberrations included numerical changes, chromosome breakage, the formation of circular chromosomal structures, chromosome fusions, and extrachromosomal elements.

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Keywords

aberrations
 
additional chromosomal aberrations
 
c-Myc protein levels
 
deregulated expression
 
DHFR
 
dihydrofolate reductase
 
experimental regulation
 
extrachromosomal elements
 
genomic stability
 
Myc protein levels
 
MycER activation
 
non-random locus-specific amplification
 
Rat1A-MycER cells
 
Rat1A-Mycer cells exhibited irreversible chromosomal aberrations
 

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