Pyrophosphoproteomics as a tool to investigate the cross-talk between inositol pyrophosphates and the DNA damage response in budding yeast

• Grant number: 23/09910-1
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• Start date: January 08, 2024
• End date: January 07, 2025
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: José Renato Rosa Cussiol
• Grantee: Giovanna Marques Panessa
• Supervisor: Marcus Bustamante Smolka
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Institution abroad: Cornell University, United States
• Associated to the scholarship: 21/04887-6 - The role of inositol metabolism and its phosphorylate derivatives in the response to genomic damage in Saccharomyces cerevisiae, BP.DD

Abstract

Inositol pyrophosphates are energy-rich signaling molecules derived from inositol conserved from yeast to humans. They regulate and control cellular homeostasis by modulating cellular responses through interactions with target proteins via two distinct mechanisms: i) allosteric interactions with protein domains such as PH (Pleckstrin Homology) domains, and ii) non-enzymatic pyrophosphorylation. The modulation of metabolic processes in which pyrophosphates act is of increasing biological relevance, considering the implications for human diseases such as neurological syndromes, diabetes, obesity, and cancer, in which inositol derivatives play a role. Recently, there has been a growing number of articles proposing crosstalk between the PP-IP pathway and the DNA damage response (DDR). Notably, it has been suggested that inositol pyrophosphate kinase Kcs1 (an ortholog of human IP6K1/2/3) modulates homologous recombination repair in budding yeast and humans. In line with that, the results obtained thus far in my PhD project demonstrate that kcs1D cells exhibit exquisite sensitivity to genotoxins, leading to increased Rad53 activation and gamma-H2A formation, indicative of persistent DNA damage in these cells. These findings suggest that PP-IPs may modulate the DDR through an unknown mechanism. Therefore, we aim to investigate, using a quantitative phosphoproteomic approach, whether the deletion of Kcs1 leads to changes in the phosphoproteome/pyrophosphoproteome profile of budding yeast cells under genotoxic stress induced by zeocin, a radiomimetic drug. We anticipate that the results obtained through this approach will help unravel the importance of this post-translational modification in modulating the DDR. (AU)