| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | ADVANCED SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1-binding protein, p122/RhoGAP, is localized in caveolin-enriched membrane domains and regulates caveolin internalization
1 Department of Life Science, Graduate School of Science, Himeji Institute of Technology, Harima Science Garden City, Hyogo 678-1297, Japan
2 Department of Biomolecular Sciences, Institute of Biomedical Sciences, Fukushima Medical College, Hikariga-oka, Fukushima 960-1295, Japan
A GTPase activating protein (GAP), p122, has previously been cloned as a phospholipase C (PLC)
1-interacting protein. p122 shows a specific GAP activity for Rho and enhances the enzyme activity of PLC1. In this study, we examined the localization and functions of p122/RhoGAP, using enhanced green fluorescent protein (EGFP)-tagged proteins. EGFP-p122 was observed as punctate structures at the plasma membrane of BHK (fibroblastic) cells and MDCK (epithelial) cells. This patchy distribution depended on membrane cholesterol levels and the C-terminal region of p122 containing the GAP domain was responsible for it. Sucrose density gradient centrifugation and immunostaining of caveolin-1 revealed that p122 was localized in caveolin-enriched membrane domains mainly via its GAP domain. We demonstrated that transient expression of EGFP-p122 caused internalization of caveolin-1. Moreover, when the EGFP-tagged GAP domain was introduced in another fibroblastic cell line, NRK cells, punctate fluorescent structures were co-localized with caveolin-1. In this case, caveolin-1-positive structures were found in patches of F-actin, unlike those of untransfected cells that formed linear arrays along with actin stress fibres. These results suggest that p122 is localized in caveolae and plays an important role in caveolin distribution through reorganization of the actin cytoskeleton.
*Correspondence: E-mail: yagisawa{at}sci.himeji-tech.ac.jp
This article has been cited by other articles:
|
|
 |
|
  T. Y. Kim, K. D. Healy, C. J. Der, N. Sciaky, Y.-J. Bang, and R. L. Juliano Effects of Structure of Rho GTPase-activating Protein DLC-1 on Cell Morphology and Migration J. Biol. Chem., November 21, 2008; 283(47): 32762 - 32770. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y.-C. Liao, Y.-P. Shih, and S. H. Lo Mutations in the Focal Adhesion Targeting Region of Deleted in Liver Cancer-1 Attenuate Their Expression and Function Cancer Res., October 1, 2008; 68(19): 7718 - 7722. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. J. Clarke, S. Forman, J. Pritchett, V. Ohanian, and J. Ohanian Phospholipase C-{delta}1 modulates sustained contraction of rat mesenteric small arteries in response to noradrenaline, but not endothelin-1 Am J Physiol Heart Circ Physiol, August 1, 2008; 295(2): H826 - H834. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 X. Qian, G. Li, H. K. Asmussen, L. Asnaghi, W. C. Vass, R. Braverman, K. M. Yamada, N. C. Popescu, A. G. Papageorge, and D. R. Lowy Oncogenic inhibition by a deleted in liver cancer gene requires cooperation between tensin binding and Rho-specific GTPase-activating protein activities PNAS, May 22, 2007; 104(21): 9012 - 9017. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Tosun, Y. Erac, C. Selli, and N. Karakaya Sarcoplasmic-endoplasmic reticulum Ca2+-ATPase inhibition prevents endothelin A receptor antagonism in rat aorta Am J Physiol Heart Circ Physiol, April 1, 2007; 292(4): H1961 - H1966. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y.-C. Liao, L. Si, R. W. deVere White, and S. H. Lo The phosphotyrosine-independent interaction of DLC-1 and the SH2 domain of cten regulates focal adhesion localization and growth suppression activity of DLC-1 J. Cell Biol., January 1, 2007; 176(1): 43 - 49. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. Hunter and G. F. Nixon Spatial Compartmentalization of Tumor Necrosis Factor (TNF) Receptor 1-dependent Signaling Pathways in Human Airway Smooth Muscle Cells: LIPID RAFTS ARE ESSENTIAL FOR TNF-{alpha}-MEDIATED ACTIVATION OF RhoA BUT DISPENSABLE FOR THE ACTIVATION OF THE NF-{kappa}B AND MAPK PATHWAYS J. Biol. Chem., November 10, 2006; 281(45): 34705 - 34715. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. W. P. Yam, F. C. F. Ko, C.-Y. Chan, D.-Y. Jin, and I. O.-L. Ng Interaction of Deleted in Liver Cancer 1 with Tensin2 in Caveolae and Implications in Tumor Suppression. Cancer Res., September 1, 2006; 66(17): 8367 - 8372. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. Hers, M. Wherlock, Y. Homma, H. Yagisawa, and J. M. Tavare Identification of p122RhoGAP (Deleted in Liver Cancer-1) Serine 322 as a Substrate for Protein Kinase B and Ribosomal S6 Kinase in Insulin-stimulated Cells J. Biol. Chem., February 24, 2006; 281(8): 4762 - 4770. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. Alpy and C. Tomasetto Give lipids a START: the StAR-related lipid transfer (START) domain in mammals J. Cell Sci., July 1, 2005; 118(13): 2791 - 2801. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. D. Stallings, E. G. Tall, S. Pentyala, and M. J. Rebecchi Nuclear Translocation of Phospholipase C-{delta}1 Is Linked to the Cell Cycle and Nuclear Phosphatidylinositol 4,5-Bisphosphate J. Biol. Chem., June 10, 2005; 280(23): 22060 - 22069. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | ADVANCED SEARCH | TABLE OF CONTENTS |
