| Project/Area Number |
11680691
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Cell biology
|
|---|
| Research Institution | Graduate School, Tokyo Medical and Dental University |
|---|
Principal Investigator |
NAKAJIMA Takuma Graduate School, Tokyo Medical and Dental University, Molecular Cellular Oncology and Microbiology Associate Professor, 大学院・医歯学総合研究科, 助教授 (90256678)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
TSUCHIDA Nobuo Graduate School, Tokyo Medical and Dental University, Molecular Cellular Oncology and Microbiology Professor, 大学院・医歯学総合研究科, 教授 (60089951)
|
|---|
| Project Period (FY) |
1999 – 2000
|
| Project Status |
Completed (Fiscal Year 2000)
|
| Budget Amount *help |
¥3,700,000 (Direct Cost: ¥3,700,000)
Fiscal Year 2000: ¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1999: ¥1,900,000 (Direct Cost: ¥1,900,000)
|
|---|
| Keywords | Id / apoptosis / Adenovirus / E1A / p53 / cell cycle / transcription / interaction / アポトーシス / HLH蛋白 / 癌 / アデノウイルスE1A / 細胞周期 / DNA複製 |
|---|
| Research Abstract |
Induction of apoptosis by adenovirus E1A in rodent cells is stimulated by wild type (wt) p53 but completely suppressed by mutated p53. The suppression is overcome by coexpression with Id proteins (Ids). The cells expressing E1A and Ids undergo apoptosis after accumulation in S phase, suggesting that S phase events are perturbed by E1A and Ids. The E1A domains required for induction of apoptosis, analyzed by transfection with expression vectors for E1A, Ids and their mutants, followed by flow cytometry, reside in N-terminal (positions 17-38), CR1 and CR2 regions. Interaction of E1A with Ids requires the N-terminal and CR1 regions. The cyclin D1 promoter activity in S phase was reduced severely by E1A and this reduction is caused through CR1 and CR2 regions required for interaction with pRB.Analysis of DNA synthesis in G2/M arrested cells indicated that E1A is capable of inducing>4N cells and this E1A-mediated DNA rereplication is enhanced by coexpression with Id-1H.The E1A domains required for induction of DNA rereplication coincide with those required for apoptosis. To analyze the concrete function of Id proteins, we tried to establish cell lines that carry inducible Id genes. To achieve this purpose, we employed the Tet-Off^<TM> gene expression system (Clontech) since this system had been thought as the best system to suppress the unexpected expression of the gene of interest until induction. However, in spite of great deal of the trials, it has not been successful. It may caused by a severe abrogation of cellular homeostasis induced by a leaky expression of introduced Id genes.
|
