Guanine Nucleotide Exchange Factors for Rho GTPases in endothelial - PowerPoint PPT Presentation

Guanine Nucleotide Exchange Factors for Rho GTPases in endothelial cells: Critical transducers of angiogenic signals JOSÉ VÁZQUEZ-PRADO, Ph.D. Pharmacology Department CINVESTAV-IPN jvazquez@cinvestav.mx

α -GTP β γ β γ α -GDP VEGF Rho SDF-1 GEF Rac GEF Tumor induced angiogenesis requires endothelial cell migration Endothelial RhoGEFs are potential targets to interfere with tumor induced angiogenesis

Rho GTPases: Promote actin polimerization and cell migration Rac Cdc42 61 human RhoGEFs (http://smart.embl-heidelberg.de/). > 40 are expressed in endothelial cells. One of them is P-Rex1 Rho Science 1998, V ol. 279,

P-Rex1

• and their partners ? • RhoGEFs • RhoGEF-interacting Rac S1P 1 , proteins GTP CXCR4 PI3K AKT β γ Rac GTP P-Rex1 DEP PDZ DH DEP PDZ PH Rac Rac GTP GDP

S1P , HGF Experimental SDF1 approach AKT PI3K β γ PhLP-1-149 BAG5 mTorC2 GRp58 shRNA mTor shRNA P-Rex1 P-Rex1 DH DEP DEP PDZ PDZ PH ∆ -DH P-Rex1 PRKAR1A Y2H PKA Rac Rac GTP GDP ? Rac S1P 1 , GTP CXCR4

P-Rex1- Rac interacting S1P 1 , GTP proteins? CXCR4 P-Rex1 P-Rex1 P-Rex1 DEP-DEP p53 DEP-DEP DEP-DEP p53 p53 pTD-11 mTor prey -LT -HLT -AHLT Y2H X α -Gal X α -Gal mTORC1 mTORC2 Hernandez-Negrete et al, 2007. J Biol Chem. 282. 23708

P-Rex1-mTOR Rac complex S1P 1 , GTP CXCR4 ? mTORC1 mTORC2 Hernandez-Negrete et al, 2007.J Biol Chem. 282. 23708

Conclusions: GRp58 VEGF SDF-1 More than 40 RhoGEFs are P-Rex1 plays a role in the signaling expressed in endothelial cells, pathway downstream of SDF1/CXCR4 Their multidomain architecture leading to Rac activation, cell migration suggest a potential role as signal and in vitro angiogenesis. integrators and therapeutic targets. This GEFs is activated in response to G β γ → PI3K γ and AKT → mTor →

Future studies: Future studies: � Relevant protein Relevant protein- -protein interactions in live protein interactions in live cells. cells. � RhoGEFs in endothelial cells from cancer RhoGEFs in endothelial cells from cancer patients? patients? � RhoGEFs in mice models of cancer RhoGEFs in mice models of cancer

Acknowledgments: Former Ph.D students: Collaborators, Group, 2009 Ivette Hernández Ivette Hernández- -Negrete Negrete Guadalupe Reyes- Guadalupe Reyes -Cruz, Cruz, Cinvestav Cinvestav Lab35F Pharmacology, Cinvestav Alejandro Garcia- Alejandro Garcia -Regalado Regalado Former M.S. students: José Vázquez-Prado Claudia Gonzalez- Claudia Gonzalez -Espinosa, Espinosa, Cinvestav Sandra Sanchez- Sandra Sanchez -Barbosa Barbosa Cinvestav jvazquez@cinvestav.mx Marina Macias- Marina Macias -Silva Silva , IFC Jonathan García- Jonathan García -Román Román , IFC- -UNAM UNAM Ana Luisa Esparza- Ana Luisa Esparza -Silva Silva Posdoctoral fellows, Silvio Gutkind, Silvio Gutkind, NIDCR NIDCR- -NIH NIH Liseth Aldaba- Liseth Aldaba -Muruato Muruato Aleida Vázquez-Macias Joan Heller Brown Joan Heller Brown , UCSD , UCSD María Luisa Guzmán María Luisa Guzmán- -Hernández. Hernández. Ph.D. students, Alejandro Ledezma- Alejandro Ledezma -Sánchez. Sánchez. Jorge Carretero Jorge Carretero- -Ortega. Ortega. Gelasio Zarco Gelasio Zarco- -Espinosa, Espinosa, IMSS IMSS- -CMN SXXI CMN SXXI Iliana Ramirez Iliana Ramirez- -Rangel. Rangel. Gabriela Hernandez Gabriela Hernandez- -Rivera, Rivera, INNSZ INNSZ Ismael Bracho Ismael Bracho- -Valdés Valdés Ricardo Hernández- Ricardo Hernández -Garc García. a. Lydia Chavez- Lydia Chavez -Vargas Vargas Evelyn Robles- Evelyn Robles -Molina Molina Israel Valencia- Israel Valencia -Martinez Martinez Grants: CONACyT, CONACyT, Technician: National Institutes of Health, USA National Institutes of Health, USA Estanislao Escobar- Estanislao Escobar -Islas Islas UC- UC -Mexus, Mexus, Lab assistant: David Pérez- David Pérez -Rangel Rangel