Interacting proteins of protein kinase A regulatory

FIORELLA GALELLO; SILVIA MORENO; SILVIA ROSSI

JOURNAL OF PROTEOMICS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2014 vol. 109 p. 261 - 275

1874-3919

cAMP-dependent protein kinase mediates many extracellular signals in eukaryotes. Thecompartmentalization of PKA is an important level of control of the specificity of signaltransduction mediated by cAMP. Unlike mammalian PKA for which proof insights in themechanism that controls its localization through anchoring proteins (AKAPs) has beenobtained, in the case of Saccharomyces cerevisiae PKA there was little information available.In this work, we present results that demonstrate the isolation and identification of yeastPKA regulatory subunit (Bcy1) associated proteins using a MS-based proteomic analysis anda bioinformatic approach. The verification of some of these interactions was assessed byimmunoprecipitation, pull down and co-localization by subcellular fractionation. The keyrole of positively charged residues present in the interaction domain of the identifiedproteins was demonstrated. The defined interaction domain has therefore differentmolecular characteristics than conventional AKAP domains. Finally we assess initialexperiments to visualize the physiological relevance of the interaction of both Ira2 andHsp60 with Bcy1. Bcy1 interacts with Ira2 tethering PKA to the Ras complex and Hsp60chaperone localizes PKA to mitochondria and has a role in the kinase stability