| Project/Area Number |
03680226
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
分子遺伝学・分子生理学
|
|---|
| Research Institution | Aichi Cancer Center Research Institute |
|---|
Principal Investigator |
NAKASU Sho Aichi cancer center research institute, Lab. of Mol. Biol., researcher, 分子生物学研究室, 研究員 (50198107)
|
|---|
| Project Period (FY) |
1991 – 1993
|
| Project Status |
Completed (Fiscal Year 1993)
|
| Budget Amount *help |
¥2,400,000 (Direct Cost: ¥2,400,000)
Fiscal Year 1993: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1992: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1991: ¥600,000 (Direct Cost: ¥600,000)
|
|---|
| Keywords | S phase / replicon / origin / レプリコン / 同調法 / F因子ベクタ- |
|---|
| Research Abstract |
The five DNA fragments which replicate early in S phase in cells synchronized with hydroxyurea were cloned from DNA of rat NRK cells digested with Hind III or Bam HI.The proportion of the cells in the synchronized culture replicated these cloned DNA was less than 10% when the amount of the total genomic DNA replicated was about 1% in the culture, while neither the replication of PCNA gene nor UDPGTase gene were detectable in the culture. The result suggest that there is a distinction between DNA regions which could be replicated early in S phase and those could not, though the former are not replicated in all cells at the same time.
The genomic clones around the one (named E1-7H) of the five clones were isolated. The three genomic clones covered about 60kb DNA region. The amount of replicated DNA were compared amoung Bam HI and/or Hind III fragments in the cloned DNA, when the nascent DNA fragments were not more than 20 kb in cells synchronized with hydroxyurea and aphidicholin. The six DNA fragments (probe A to F from left side to right side) spanning about 40 kb DNA region were used as probes. The amount of replicated DNA from two fragments hybridized with probe C and F were high compared with that of the fragment between them. However the amount of replicated DNA fragment from the other side of the fragment hybridized with probe C did not decline significantly in the same culture. These results could not be explained with the model that mammalian replicons are 30 to 200 kb region with the unique initiation site of DNA replication.
|
