title: AT₂receptors recruit c-Src, SHP-1 and FAK upon activation by Ang II in PND15 rat hindbrain.
abstract: The functional role of AT(2) receptors is unclear and it activates unconventional signaling pathways, which in general do not involve a classical activation of a G-protein. In the present study, we aimed to investigate the transduction mechanism of AT(2) Ang II receptors in PND15 rat hindbrain membrane preparations, which represents a physiological developmental condition. To determine whether Ang II AT(2) receptors induced association to SHP-1 in rat hindbrain, co-immunoprecipitation assays were performed. Stimulation of Ang II AT(2) receptors induced both a transient tyr-phosphorylation and activation of SHP-1. The possible participation of c-Src in Ang II-mediated SHP-1 activation, we demonstrated by recruitment of c-Src in immunocomplexes obtained with anti AT(2) or anti-SHP-1 antibodies. The association of SHP-1 to c-Src was inhibited by PD123319 and the c-Src inhibitor PP2. Similarly, SHP-1 activity determined in AT(2)-immunocomplexes was inhibited by PD123319 and the c-Src inhibitor PP2. Following stimulation with Ang II, AT(2) receptors recruit c-Src, which was responsible for SHP-1 tyr-phosphorylation and activation. Since AT(2) receptors are involved in neuron migration, we tested the presence of FAK in immunocomplexes. Surprisingly, AT(2)-immunocomplexes contained mainly the 85kDa fragment of FAK. Besides, p125FAK associated to SHP-1. In summary, we demonstrated the presence of an active signal transduction mechanism in PND15 rat hindbrain, a developmental stage critical for cerebellar development. In this model, we showed a complex containing AT(2)/SHP-1/c-Src/p85FAK, suggesting a potential role of Ang II AT(2) receptors in cerebellar development and neuronal differentiation.
authors: Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO-SL CONICET), Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina.
authors: Leonardo R
authors: LR
authors: Seguin
authors: Rodrigo S
authors: RS
authors: Villarreal
authors: Gladys M
authors: GM
authors: Ciuffo
mesh_terms: D000804:Angiotensin II / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn; D000081247:CSK Tyrosine-Protein Kinase; D002465:Cell Movement / Q000502:physiology; D002531:Cerebellum / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D051417:Focal Adhesion Kinase 1 / Q000737:chemistry / Q000378:metabolism*; D046911:Macromolecular Substances / Q000378:metabolism; D055495:Neurogenesis / Q000187:drug effects / Q000502:physiology; D010766:Phosphorylation / Q000502:physiology; D021381:Protein Transport / Q000502:physiology; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D044139:Receptor, Angiotensin, Type 2 / Q000819:agonists / Q000502:physiology*; D012249:Rhombencephalon / Q000166:cytology* / Q000201:enzymology / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D019061:src-Family Kinases
chemical_list: D046911:Macromolecular Substances; D044139:Receptor, Angiotensin, Type 2; D000804:Angiotensin II; D011505:Protein-Tyrosine Kinases; D000081247:CSK Tyrosine-Protein Kinase; D051417:Focal Adhesion Kinase 1; C496052:Ptk2 protein, rat; D019061:src-Family Kinases; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; C509250:Ptpn6 protein, rat