Mitochondrial and nuclear kinase complex: Role of MAKPs and MKPs in the cyclic AMP-mediated response

PODEROSO, C, DUARTE A, BRION L, GOMEZ NV, MORI SEQUEIROS GARCÍA MM, PODESTÁ EJ, PAZ C

San Miguel de Tucumán, Tucumán, Argentina

Congreso; XLIV Reunión Anual SAIB; 2009

SAIB

Protein phosphorylation mediated by the concerted action of kinases and phosphatases regulates key biological events such as cell growth, differentiation and apoptosis. The simultaneous stimulation of different signal pathways to produce several cellular responses involves a finite number of kinases and phosphatases. Thus, the spatial and temporal control of these enzymes is crucial for the selectivity and effectiveness of phospho/dephosphorylation events. The regulation of MAP kinases (MAPKs) and MAP kinase phosphatases (MKPs) which provides a negative feedback mechanism for MAP kinase activity, explains how this control is achieved. Phosphorylation induced by a specific stimulus promotes conformational changes, create docking sites and causes intracellular relocation of proteins that finally resulta in the activation of a particular set of MAPKs in a specific compartment. The same stimulus also induces MKPs of different induction kinetics and subcellular localization. Thus, these coordinated events and the existence of a complex containing  a specific substrate with kinases, phosphatases, docking and scaffolding proteins leads to the compartment specific regulaon of MAPKs to produce the right sponse in the right place. Here, the participation of nuclear and mitochondrial kinases and phosphatases complex in the induction and activation of key steroidogenic proteins will be presented.