| Project/Area Number |
16590239
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Pathological medical chemistry
|
|---|
| Research Institution | Yamagata University (2005)
University of Tsukuba (2004) |
|---|
Principal Investigator |
BANNAI Shiro Yamagata University, Faculty of Agriculture, Visiting Professor, 農学部, 客員教授 (70019579)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SATO Hideyo Yamagata University, Faculty of Agriculture, Associate Professor, 農学部, 助教授 (60235380)
|
|---|
| Project Period (FY) |
2004 – 2005
|
| Project Status |
Completed (Fiscal Year 2005)
|
| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2005: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2004: ¥2,700,000 (Direct Cost: ¥2,700,000)
|
|---|
| Keywords | Cystine / Glutamate / Transporter / Glutathione / Gene-knockout mouse / Redox / 国際情報交換 / ドイツ / 遺伝子ノックアウト / 酸化ストレス |
|---|
| Research Abstract |
Transport system x_c^- mediates the exchange transport between extracellular cystine and intracellular glutamate. This system is composed of two proteins, xCT and 4F2hc, and the former is thought to be the actual transporter. In this project we have tried to produce xCT gene-knockout (xCT^<-/->) mouse to elucidate the physiological and pathological role of system x_c^- in whole mouse. The results are as follows :
1. xCT^<-/-> mice have been successfully produced. Mice homozygous for the targeted disruption of the xCT gene were identified by PCR and genomic Southern blot analysis. Activity of cystine transport via system x_c^- was completely lost in these mice.
2. xCT^<-/-> mice, until six months after birth, were apparently healthy in appearance and fertile.Microscopically no abnormalities were found in any of the organs tested and, in hematological investigations, no abnormalities were found in these mice.
3. We have examined plasma amino acids. Cystine concentration in xCT^<-/-> mice is significantly higher than in wild type mice while there was no difference in plasma cysteine concentration. Plasma glutathione (GSH) level in xCT^<-/-> mice was lower than that in wild type mice. These results suggest redox imbalance in xCT^<-/-> mice.
4. The embryonic fibroblasts derived from xCT^<-/-> mice failed to survive in routine culture medium. GSH in the cells from xCT^<-/-> mice drastically decreased during the culture and this may cause cell death.
5. We could not find any difference between the survival rate of xCT^<-/-> and wild type mice under conditions of oxidant stress or of inflammatory stimulus.
6. We have investigated a phenotype change of xCT^<-/-> mice over six month after birth. However, the experiments have not been completed due to a restriction by time.
|
