Previous Article | Next Article 
Molecular and Cellular Biology, April 2002, p. 2487-2497, Vol. 22, No. 8
0270-7306/02/$04.00+0 DOI: 10.1128/MCB.22.8.2487-2497.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.
Critical but Distinct Roles for the Pleckstrin Homology and Cysteine-Rich Domains as Positive Modulators of Vav2 Signaling and Transformation
Michelle A. Booden,1* Sharon L. Campbell,2 and Channing J. Der1
Department of Pharmacology,1
Department of Biochemistry and Biophysics, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 275992
Received 4 October 2001/
Returned for modification 2 November 2001/
Accepted 9 January 2002
Vav2, like all Dbl family proteins, possesses tandem Dbl homology (DH) and pleckstrin homology (PH) domains and functions as a guanine nucleotide exchange factor for Rho family GTPases. Whereas the PH domain is a critical positive regulator of DH domain function for a majority of Dbl family proteins, the PH domains of the related Vav and Vav3 proteins are dispensable for DH domain activity. Instead, Vav proteins contain a cysteine-rich domain (CRD) critical for DH domain function. We evaluated the contribution of the PH domain and the CRD to Vav2 guanine nucleotide exchange, signaling, and transforming activity. Unexpectedly, we found that mutations of the PH domain impaired Vav2 signaling, transforming activity, and membrane association. However, these mutations do not influence exchange activity on Rac and only slightly affect exchange on RhoA and Cdc42. We also found that the CRD was critical for the exchange activity in vitro and contributed to Vav2 membrane localization. Finally, we found that phosphoinositol 3-kinase activation synergistically enhanced Vav2 transforming and signaling activity by stimulating exchange activity but not membrane association. In conclusion, the PH domain and CRD are mechanistically distinct, positive modulators of Vav2 DH domain function in vivo.
* Corresponding author. Mailing address: University of North Carolina at Chapel Hill, CB 7295, Lineberger Comprehensive Cancer Center, Chapel Hill, NC 27599. Phone: (919) 962-1057. Fax: (919) 966-0162. E-mail: mbooden{at}med.unc.edu.
Molecular and Cellular Biology, April 2002, p. 2487-2497, Vol. 22, No. 8
0022-538X/02/$04.00+0 DOI: 10.1128/MCB.22.8.2487-2497.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Lyons, L. S., Rao, S., Balkan, W., Faysal, J., Maiorino, C. A., Burnstein, K. L.
(2008). Ligand-Independent Activation of Androgen Receptors by Rho GTPase Signaling in Prostate Cancer. Mol. Endocrinol.
22: 597-608
[Abstract]
[Full Text]
-
Ferraro, F., Ma, X.-M., Sobota, J. A., Eipper, B. A., Mains, R. E.
(2007). Kalirin/Trio Rho Guanine Nucleotide Exchange Factors Regulate a Novel Step in Secretory Granule Maturation. Mol. Biol. Cell
18: 4813-4825
[Abstract]
[Full Text]
-
Lyons, L. S., Burnstein, K. L.
(2006). Vav3, a Rho GTPase Guanine Nucleotide Exchange Factor, Increases during Progression to Androgen Independence in Prostate Cancer Cells and Potentiates Androgen Receptor Transcriptional Activity. Mol. Endocrinol.
20: 1061-1072
[Abstract]
[Full Text]
-
Jonkers, Y M H, Claessen, S M H, Perren, A, Schmid, S, Komminoth, P, Verhofstad, A A, Hofland, L J, de Krijger, R R, Slootweg, P J, Ramaekers, F C S, Speel, E-J M
(2005). Chromosomal instability predicts metastatic disease in patients with insulinomas. Endocr Relat Cancer
12: 435-447
[Abstract]
[Full Text]
-
Miller, S. L., DeMaria, J. E., Freier, D. O., Riegel, A. M., Clevenger, C. V.
(2005). Novel Association of Vav2 and Nek3 Modulates Signaling through the Human Prolactin Receptor. Mol. Endocrinol.
19: 939-949
[Abstract]
[Full Text]
-
Arthur, W. T., Quilliam, L. A., Cooper, J. A.
(2004). Rap1 promotes cell spreading by localizing Rac guanine nucleotide exchange factors. J. Cell Biol.
167: 111-122
[Abstract]
[Full Text]
-
Solski, P. A., Wilder, R. S., Rossman, K. L., Sondek, J., Cox, A. D., Campbell, S. L., Der, C. J.
(2004). Requirement For C-terminal Sequences in Regulation of Ect2 Guanine Nucleotide Exchange Specificity and Transformation. J. Biol. Chem.
279: 25226-25233
[Abstract]
[Full Text]
-
Carrasco, S., Merida, I.
(2004). Diacylglycerol-dependent Binding Recruits PKC{theta} and RasGRP1 C1 Domains to Specific Subcellular Localizations in Living T Lymphocytes. Mol. Biol. Cell
15: 2932-2942
[Abstract]
[Full Text]
-
Fuentes, E. J., Karnoub, A. E., Booden, M. A., Der, C. J., Campbell, S. L.
(2003). Critical Role of the Pleckstrin Homology Domain in Dbs Signaling and Growth Regulation. J. Biol. Chem.
278: 21188-21196
[Abstract]
[Full Text]
-
Baumeister, M. A., Martinu, L., Rossman, K. L., Sondek, J., Lemmon, M. A., Chou, M. M.
(2003). Loss of Phosphatidylinositol 3-Phosphate Binding by the C-terminal Tiam-1 Pleckstrin Homology Domain Prevents in Vivo Rac1 Activation without Affecting Membrane Targeting. J. Biol. Chem.
278: 11457-11464
[Abstract]
[Full Text]
-
Cote, J.-F., Vuori, K.
(2003). Identification of an evolutionarily conserved superfamily of DOCK180-related proteins with guanine nucleotide exchange activity. J. Cell Sci.
115: 4901-4913
[Abstract]
[Full Text]
-
Tamas, P., Solti, Z., Bauer, P., Illes, A., Sipeki, S., Bauer, A., Farago, A., Downward, J., Buday, L.
(2003). Mechanism of Epidermal Growth Factor Regulation of Vav2, a Guanine Nucleotide Exchange Factor for Rac. J. Biol. Chem.
278: 5163-5171
[Abstract]
[Full Text]
-
Palmby, T. R., Abe, K., Der, C. J.
(2002). Critical Role of the Pleckstrin Homology and Cysteine-rich Domains in Vav Signaling and Transforming Activity. J. Biol. Chem.
277: 39350-39359
[Abstract]
[Full Text]
Copyright © 2002 by the American Society for Microbiology. All rights reserved.