The most frequent genetic aberration found in transitional cell carcinoma (TCC) of the bladder involves chromosome 9. Loss of heterozygosity (LOH) analyses show deletions of both chromosome 9p and 9q, while in situ hybridization studies suggest a significant percentage of tumours with monosomy 9. To
Studies on the alteration of chromosome copy number and cell division potential in a dnaA mutant of Escherichia coli
โ Scribed by Fralick, Joe A.
- Publisher
- Springer
- Year
- 1991
- Tongue
- English
- Weight
- 589 KB
- Volume
- 229
- Category
- Article
- ISSN
- 0026-8925
No coin nor oath required. For personal study only.
โฆ Synopsis
The dnaA167 mutant of Escherichia coli, N167, maintains, on the average, two replicating chromosomes per cell at the permissive growth temperature of 30 degrees C and only one per cell at the higher permissive growth temperature of 38 degrees C. When the growth temperature of this mutant is changed from 30 degrees to 38 degrees C the cells rapidly readjust their chromosome copy number from two to one. I have examined the kinetics of this transition with reference to DNA replication and cell division. My results indicate that this mutant uncouples cell division from chromosome duplication to achieve the appropriate copy number, suggesting that the dnaA gene product may be involved in the coordination between these two cellular events.
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