2000 Fiscal Year Final Research Report Summary
Functional analysis of rice proteins which bind to the α subunit of nuclear transport complex.
| Project/Area Number |
11640645
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
植物生理
|
|---|
| Research Institution | NIIGATA UNIVERSITY |
|---|
Principal Investigator |
IWASAKI Toshisuke Niigata University, Faculty of Science, Associate Professor, 理学部, 助教授 (00201947)
|
|---|
| Project Period (FY) |
1999 – 2000
|
| Keywords | Nuclear protein / Importin α-binding protein / Light-responsive gene expression / Protein-protein interaction / Rice / Affinity chromatography / TPR sequence / Nuclear localization signal |
|---|
| Research Abstract |
The purpose of this research is to identify a novel nuclear protein which might be involved in the light-response in rice plants, by isolating proteins that bind to rice importin α 1a (IMP α 1a) whose expression is down-regulated by light. Below are the results.
1. Analysis of an IMP α 1a-binding protein, IABP4, which has been isolated by cDNA screening by Far western method.
(1) Determination of the full cDNA sequence : The IABP4 cDNA contained the entire coding sequence for a novel protein of predicted molecular mass of 122 kDa, and the homologous gene was found on the chromosome 2 of Arabidopsis thaliana.. In the N-terminal region containing TPR motifs, IABP4 protein shows high homology to a mouse nuclear phosphoprotein, TSP, whereas the similarity is low in the C-terminal region which contains the SH2-binding domain in mouse TSP, suggesting that the IABP4 protein is not necessarily homologous in function to TSP.The C-terminal part contains a putative nuclear localization signal.
(2) Analysis of gene expression : The result of RT-PCR indicated that the IABP4 transcript level decreases by illuminating dark-grown seedlings of rice.
(3) Analysis of binding to IMP α 1a : Usins purified recombinant proteins expressed in E.coil, the binding assay with native polyacrylamide gel electrophoresis demonstrated the complex formation between the C-terminal part of IABP4 and GST-IMP α 1a.
Further experiments are required for determination of nuclear localization and the in planta function of the IABP4 protein.
2. By another approach using affinity chromatography, several IMP α 1a-binding proteins were isolated from etiolated rice seedlings and the N-terminal sequences of three of them were determined. For one protein with homology to proline-rich protein, the corresponding cDNA was isolated and its expression was found to be down-regulated by light in dark-grown seedlings.
|
Research Products
(2 results)
-
-
[Publications] Jiang, C.J., Shoji, K., Matsuki, R., Baba, A., Inagaki, N., Ban, H., Iwasaki, T., Imamoto, N., Yoneda, Y., Deng, X.W., and Yamaoto, N.: "Molecular cloning of a novel importin α from rice, by which COP1 NLS-protein is preferentially nuclear imported."Journal of Biological Chemistry. (in press). (2001)
Description
「研究成果報告書概要(欧文)」より
