|
|
|
|
|
||
|
|||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
First published online May 28, 2005
doi: 10.1242/10.1242/jcs.02370
Research Article |
1 Laboratoire de Biologie du Développement, UMR-CNRS 7622, Université Pierre et Marie Curie, boîte 24, 4 place Jussieu, 75252 Paris, CEDEX 5, France
2 Centre de Recherche de Biochimie Macromoléculaire, CNRS FRE 2593, 1919 Route de Mende, 34293 Montpellier, CEDEX 5, France
3 Signal Transduction and Plasticity in the Nervous System, INSERM U-536, Université Pierre et Marie Curie, Institut du Fer-à-Moulin, 17 rue du Fer-à-Moulin, 75005 Paris, France
* Author for correspondence (e-mail: jessus{at}ccr.jussieu.fr)
Accepted 9 March 2005
The success of cell division relies on the activation of its master regulator Cdc2-cyclin B, and many other kinases controlling cellular organization, such as Aurora-A. Most of these kinase activities are regulated by phosphorylation. Despite numerous studies showing that okadaic acid-sensitive phosphatases regulate both Cdc2 and Aurora-A activation, their identity has not yet been established in Xenopus oocytes and the importance of their regulation has not been evaluated. Using an oocyte cell-free system, we demonstrate that PP2A depletion is sufficient to lead to Cdc2 activation, whereas Aurora-A activation depends on Cdc2 activity. The activity level of PP1 does not affect Cdc2 kinase activation promoted by PP2A removal. PP1 inhibition is also not sufficient to lead to Aurora-A activation in the absence of active Cdc2. We therefore conclude that in Xenopus oocytes, PP2A is the key phosphatase that negatively regulates Cdc2 activation. Once this negative regulator is removed, endogenous kinases are able to turn on the activator Cdc2 system without any additional stimulation. In contrast, Aurora-A activation is indirectly controlled by Cdc2 activity independently of either PP2A or PP1. This strongly suggests that in Xenopus oocytes, Aurora-A activation is mainly controlled by the specific stimulation of kinases under the control of Cdc2 and not by downregulation of phosphatase.
Key words: Aurora-A, Cdc2, PP1, PP2A, Xenopus oocyte
This article has been cited by other articles:
|
|
 |
|
  Y. Zhao, O. Haccard, R. Wang, J. Yu, J. Kuang, C. Jessus, and M. L. Goldberg Roles of Greatwall Kinase in the Regulation of Cdc25 Phosphatase Mol. Biol. Cell, April 1, 2008; 19(4): 1317 - 1327. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Uzbekova, Y. Arlot-Bonnemains, J. Dupont, R. Dalbies-Tran, P. Papillier, S. Pennetier, A. Thelie, C. Perreau, P. Mermillod, C. Prigent, et al. Spatio-Temporal Expression Patterns of Aurora Kinases A, B, and C and Cytoplasmic Polyadenylation-Element-Binding Protein in Bovine Oocytes During Meiotic Maturation Biol Reprod, February 1, 2008; 78(2): 218 - 233. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Horn, J. Thelu, A. Garcia, C. Albiges-Rizo, M. R. Block, and J. Viallet Functional Interaction of Aurora-A and PP2A during Mitosis Mol. Biol. Cell, April 1, 2007; 18(4): 1233 - 1241. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. T. Keady, P. Kuo, S. E. Martinez, L. Yuan, and L. E. Hake MAPK interacts with XGef and is required for CPEB activation during meiosis in Xenopus oocytes J. Cell Sci., March 15, 2007; 120(6): 1093 - 1103. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Han, L. Han, P. Tiwari, Z. Wen, and J. Q. Zheng Spatial targeting of type II protein kinase A to filopodia mediates the regulation of growth cone guidance by cAMP J. Cell Biol., January 1, 2007; 176(1): 101 - 111. [Abstract] [Full Text] [PDF]
|
|
