INTERACTING PROTEINS OF PKA REGULATORY SUBUNIT FROM SACCHAROMYCES CEREVISIAE

GALELLO FIORELLA, MORENO SILVIA AND ROSSI SILVIA

Tucuman Argentina

Congreso; SAIB - 45 rd Annual Meeting XLV Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecula; 2009

SAIB

INTERACTING PROTEINS OF PKA REGULATORY SUBUNIT FROM SACCHAROMYCES CEREVISIAE   Galello Fiorella, Moreno Silvia and Rossi Silvia. Laboratorio de Biología Molecular y Transducción de Señales, Depto Química Biológica, FCEN, UBA.   Common challenges to any cell are the processing of the extracellular stimuli it receives into intracellular signaling cascades that initiate a multitude of diverse biological functions. Subcellular targeting through the association with adaptor and scaffolding proteins has emerged as a key mechanism by which cells maintain signaling specificity. Compartmentation of cAMP signaling is maintained by the clustering of cAMP signaling enzymes in discrete units by the scaffolding protein A-kinase anchoring proteins (AKAPs) through their interaction with Regulatory subunit. Our aim is to identify S. cerevisiae  AKAPs to study PKA localization and to evaluate their participation in PKA activation . No anchoring proteins had been characterized up to now in yeast. We have identified anchoring proteins of Regulatory subunit from yeast PKA (BCY1) using TAP-affinity purification and MALDI-TOF-TOF identification. The interactions were verified by pull-downs and peptide arrays. The critical residues in the protein domain from the interacting protein were identified by Ala-scanning peptide array. We also demonstrate using BCY1 N-terminus mutants that the region 1-138 is necessary to the interaction with these proteins.