| Project/Area Number |
03304052
|
|---|
| Research Category |
Grant-in-Aid for Co-operative Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
代謝生物化学
|
|---|
| Research Institution | Gifu University |
|---|
Principal Investigator |
NOZAWA Yoshinori Gifu University, School of Medicine, Biochemistry, Professor, 医学部, 教授 (10021362)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MATSUMOTO Kunihiro Nagoya University, Faculty of Science, Molecular Biology, Professor, 理学部, 教授 (70116375)
YAMAMOTO Masayuki University of Tokyo, Faculty of Science, Cellular Molecular Biology, Professor, 理学部, 教授 (40114706)
NARUMIYA Shuh Kyoto University, School of Medicine, Pharmacology, Professor, 医学部, 教授 (70144350)
KATADA Toshiaki Tokyo Institute of Technology, Department of Life Science, Professor, 生命理工学部, 教授 (10088859)
TAKAI Yoshimi Kobe University, School of medicine, Biochemistry, Professor, 医学部, 教授 (60093514)
|
|---|
| Project Period (FY) |
1991 – 1992
|
| Keywords | Low molecular weight / GTP-binding protein / Botulinum toxin / Yeast / Mammalian / Secretion / ADP-ribosylation |
|---|
| Research Abstract |
It is well known that a variety of ras-related low Mr GTP-binding proteins are present from yeast to mammalian. We have purified and identified several kinds of low Mr GTP-binding proteins such as rhoA, rac,ram and c25KG proteins in mammalian tissues. rhoA was identified a sole substrate of botulinum C3 enzyme in human platelet and suggested to be involved in cytoskeletal regulation. We observed that the C3 enzyme-like enzyme is present in bovine brain and partially purified it. rho protein was also observed to take part in contraction of smooth muscle although the mechanism has not been totally elucidated. rac protein was reported in phagocytes to control the superoxide-generating NADPH oxidase system which consists of at least one membrane and three cytosolic components. In yeast, SAR1 plays an essential role in intracellular protein transport and RSR1 has similar function as that of mammalian homolog, rap1.
Recently, several kinds of regulatory proteins for low Mr GTP-binding proteins have been reported. GTPase activating protein for ras p21 (ras-GAP) was first purified, identified and cloned. Thereafter, we purified GAPs for smg p21 and rho p20. GDP dissociation stimulator (GDS) and GDP dissociation inhibitor (GDI) have also been purified and identified for some low Mr GTP-bining proteins such as ras p21, smg proteins, rho p20, and smg p25A. The modes of the action of these regulatory proteins on the GTP-binding proteins were investigated and it was shown that the C-terminal prenylation such as farnesylation and geranylgeranylation is necessary for their functions.
|
