![]() |
|
|
Vol. 19, Issue 6, 2650-2660, June 2008
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
Submitted October 23, 2007;
Revised March 19, 2008;
Accepted April 3, 2008
Monitoring Editor: Akihiko Nakano
BIG2 and BIG1 are closely related guanine-nucleotide exchange factors (GEFs) for ADP-ribosylation factors (ARFs) and are involved in the regulation of membrane traffic through activating ARFs and recruiting coat protein complexes, such as the COPI complex and the AP-1 clathrin adaptor complex. Although both ARF-GEFs are associated mainly with the trans-Golgi network (TGN) and BIG2 is also associated with recycling endosomes, it is unclear whether BIG2 and BIG1 share some roles in membrane traffic. We here show that knockdown of both BIG2 and BIG1 by RNAi causes mislocalization of a subset of proteins associated with the TGN and recycling endosomes and blocks retrograde transport of furin from late endosomes to the TGN. Similar mislocalization and protein transport block, including furin, were observed in cells depleted of AP-1. Taken together with previous reports, these observations indicate that BIG2 and BIG1 play redundant roles in trafficking between the TGN and endosomes that involves the AP-1 complex.
* These authors contributed equally to this work.
Address correspondence to: Kazuhisa Nakayama (kazunaka{at}pharm.kyoto-u.ac.jp)
Abbreviations used: ARF, ADP-ribosylation factor; HRP, horseradish peroxidase; GEF, guanine nucleotide exchange factor; PACS, phosphofurin acidic cluster sorting protein; TGN, trans-Golgi network; TfnR, transferrin receptor; VSVG, vesicular stomatitis virus G protein.
This article has been cited by other articles:
![]() |
Z. Xu, Q. Gong, B. Xia, B. Groves, M. Zimmermann, C. Mugler, D. Mu, B. Matsumoto, M. Seaman, and D. Ma A role of histone H3 lysine 4 methyltransferase components in endosomal trafficking J. Cell Biol., August 10, 2009; 186(3): 343 - 353. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Nishimoto-Morita, H.-W. Shin, H. Mitsuhashi, M. Kitamura, Q. Zhang, L. Johannes, and K. Nakayama Differential Effects of Depletion of ARL1 and ARFRP1 on Membrane Trafficking between the trans-Golgi Network and Endosomes J. Biol. Chem., April 17, 2009; 284(16): 10583 - 10592. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. A. K. Dehring, A. S. Adler, A. Hosseini, and L. Hicke A C-terminal Sequence in the Guanine Nucleotide Exchange Factor Sec7 Mediates Golgi Association and Interaction with the Rsp5 Ubiquitin Ligase J. Biol. Chem., December 5, 2008; 283(49): 34188 - 34196. [Abstract] [Full Text] [PDF] |
||||