Kinetic analyses of clathrin adaptor proteins involved in the Golgi-endosome trafficking
Project/Area Number |
15590159
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
General anatomy (including Histology/Embryology)
|
Research Institution | Osaka University |
Principal Investigator |
WAGURI Satoshi Osaka University, Graduate School of Medicine, Associate professor, 医学系研究科, 助教授 (30244908)
|
Project Period (FY) |
2003 – 2004
|
Project Status |
Completed (Fiscal Year 2004)
|
Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2004: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 2003: ¥2,000,000 (Direct Cost: ¥2,000,000)
|
Keywords | GFP / FRAP / live-cell imaging / trans-Golgi network / endosome / GGA / AP1 / mannose 6-phosphate receptor / リソソーム酵素 / FRAP6 / AP-1 |
Research Abstract |
To understand detailed mechanisms of the transport of lysosomal enzymes, clathrin adopter proteins, the GGAs and AP1, and the mannose 6-phosphate receptor (MPR) were fused with GFP, which were examined by live-cell imaging and FRAP (fluorescence recovery after photobleaching) analysis. Through this research project, following results were obtained. 1. GGA1 and AP1 showed different distribution patterns in the TGN (trans-Golgi network) region, and most transport carriers that left the TGN contained AP1 alone. These results suggest that GGAs and AP1 are involved in the pre- and post-budding events, respectively. 2. GGA2 repeated association and motion with the TGN membrane more rapidly than GGA1 and GGA3. Moreover, the presence of the hinge-ear domain of GGA1 retarded this cycling kinetics. 3. The presence of the extracellular domain of the cation-independent MPR may facilitate the fusion of the TGN-derived transport carvers containing the MPR with endosomes, and retain the MPR in the peripheral region for longer periods. Followings are results obtained in relation to this research project. 1. A splice-variant of GGA3 was predominantly expressed in several human tissues except brain, and human-derived culture cell lines. Because the variant form lacks a binding site for MPR, GGA3 may play a new role other than the MPR trafficking. 2. U18666A treatment caused an accumulation of MPR in aberrant endosomal structures. This redistribution may associate with ligand-dependent transport steps of MPR.
|
Report
(3 results)
Research Products
(13 results)