Development and standardization of a new methodology to evaluate the effect of intracellular peptides on protein-protein interactions

• Grant number: 18/07852-6
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: June 01, 2018
• End date: February 28, 2019
• Field of knowledge: Biological Sciences - Pharmacology - Biochemical and Molecular Pharmacology
• Principal Investigator: Emer Suavinho Ferro
• Grantee: Tiago Zaminelli
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 16/04000-3 - Pharmacology of oligopeptidases and intracellular peptides, AP.TEM

Abstract

Proteins are fundamental to the physiological dynamics of life, forming interactive networks that respond to spatial and temporal circumstances (eg, environmental conditions, stress or pathological situations or drug action). Proteins do not act alone but interact with each other by participating in a series of physiological modulations. These interactions protein (s) -protein (s) can be dynamic or stable, and occur through physical-chemical structural mechanisms controlled by the structural and cellular microenvironment. Due to the dynamics and complexity of these reactions, the ideal when analyzed is that the analytical methods used will disturb the natural cellular context.Among the vast variety of proteins and peptidases suggested to regulate protein-protein interactions are thimet oligopeptidase (EC 3.4.24.15; EP24.15). This enzyme is notable for its presence in both the intracellular and extracellular compartments, where it metabolizes several peptides (degraded and produced) produced by the proteasome or the secretory pathway (i.e., neuropeptides). EP24.15 participates in the network of cellular interactions interacting, for example, with 14-3-3 epsilon in a manner dependent on phosphorylation at serine 644 by protein kinase A (Carreño ET AL., 2005). On the other hand, EP24.15 has also been suggested to participate in the network of cellular protein interactions by metabolizing intracellular peptides (Cunha ET AL., JBC 2008; Russian ET AL., FEBS Letters, 2012).Therefore, our challenge in this project is to develop and validate an experimental protocol that allows the quantification of interactions between proteins in vivo (in cells and / or animals), that can be applied to determine the effect of specific intracellular peptides, or of global changes in the intracellular composition of peptides.