Biochemical studies of DUSP12 phosphatase under conditions of genotoxic stress: bimolecular interactions and enzymatic activity

• Grant number: 22/10958-6
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: May 01, 2023
• End date: February 28, 2027
• Field of knowledge: Biological Sciences - Genetics - Mutagenesis
• Principal Investigator: Fábio Luis Forti
• Grantee: Diana Reis Della Corte Guimarães Pacheco
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Protein tyrosine phosphatases (PTPs) act by dephosphorylating tyrosine residues in different biomolecules and, therefore, their activity regulates the course of cellular processes physiologically essential. Dual-specificity PTPs (DUSPs) can dephosphorylate tyrosine and threonine/serine residues, thus acting on a greater variety of substrates and, consequently, being involved in several diseases caused by deregulation of these enzymes. Neurodegenerative, autoimmune, and cancer diseases depend on the action of DUSPs, which are overexpressed or modified on them. Among these enzymes is DUSP12, recently correlated with manifestations of hepatocarcinoma, chronic myeloid leukemia, and osteosarcoma. Our group reported the interaction of DUSP12 with HP1BP3 and NAT10 proteins, which are involved in fundamental cellular processes such as genomic stability, gene transcription, and cytokinesis. These findings can provide more information about the mechanisms relating these three proteins and enable new strategies for the pharmacological treatment of these and other disorders. The purpose of this work is to investigate kinetic and structural parameters of this atypical dual-specificity phosphatase through different approaches to identify which domains of this enzyme have the greater influence on its phosphatase activity, and furthermore if they are affected by various stress conditions. With this information in hand, investigative analyzes will be performed on the interaction of DUSP12 with the two protein partners already identified by mass spectrometry (HP1BP3 and NAT10) through assays involving tumor cells under genotoxic stress conditions. The success of these investigations can directly impact the knowledge mechanisms in the establishment and development of cancer through therapeutic use of drugs that act by interfering with the activity and/or protein-protein interactions of DUSP12. (AU)