DNA replication initiates non-randomly at multiple sites near the c-myc gene in HeLa cells.
AUTOR(ES)
Waltz, S E
RESUMO
The origin of replication of the c-myc gene in HeLa cells was previously identified at low resolution within 3.5 kb 5' to the P1 promoter, based on replication fork polarity and the location of DNA nascent strands. To define the initiation events in the c-myc origin at higher resolution the template bias of nascent DNAs in a 12 kb c-myc domain has been analyzed by hybridization to strand specific probes. Strong switches in the asymmetry of nascent strand template preference confirm that replication initiates non-randomly at multiple sites within 2.4 kb 5' to the c-myc P1 promoter, and at other sites over a region of 12 kb or more. The strongest template biases occur in the 2.4 kb region 5' of the P1 promoter, shown earlier to contain sequences which allow the autonomous semiconservative replication of c-myc plasmids. An asymmetric pyrimidine heptanucleotide consensus sequence has been identified which occurs 12 times in the c-myc origin zone, and whose polarity exactly correlates with the polarity of nascent strand synthesis.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=145880Documentos Relacionados
- An initiation zone of chromosomal DNA replication located upstream of the c-myc gene in proliferating HeLa cells.
- Evidence that a triplex-forming oligodeoxyribonucleotide binds to the c-myc promoter in HeLa cells, thereby reducing c-myc mRNA levels.
- Opposite replication polarity of the germ line c-myc gene in HeLa cells compared with that of two Burkitt lymphoma cell lines.
- DNA replication origin and transcriptional enhancer in c-myc gene share the c-myc protein binding sequences.
- Analysis of premature termination in c-myc during transcription by RNA polymerase II in a HeLa nuclear extract.