UNRAVELING THE FUNCTIONS OF UCH-L1 UBIQUITINATION IN THE CELL

• Grant number: 24/05737-6
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Effective date (Start): September 01, 2024
• Effective date (End): February 28, 2025
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Ângela Saito
• Grantee: Silas Pontes Almeida
• Supervisor: Gustavo Monteiro Silva
• Host Institution: Centro Nacional de Pesquisa em Energia e Materiais (CNPEM). Ministério da Ciência, Tecnologia e Inovação (Brasil). Campinas , SP, Brazil
• Research place: Duke University, United States
• Associated to the scholarship: 22/16211-0 - FUNCTIONAL AND STRUCTURAL CHARACTERIZATION OF THE INTERACTION BETWEEN UBE2A AND UBIQUITINATION PATHWAY PROTEINS ASSOCIATED WITH NEUROLOGICAL DISORDERS, BP.MS

Abstract

UBE2A is an ubiquitin-conjugating enzyme key component of the ubiquitination pathway and has been reported to act in several processes, such as DNA repair, maintenance of genomic integrity, regulation of p53 expression, removal of dysfunctional mitochondria and regulation of proteasome activity. The Q93E mutation in UBE2A, found in Brazilian patients, can directly interfere with its activity, and have been associated with the X-linked Intellectual Disability type Nascimento (XLIID) syndrome. Global ubiquitinome analyses comparing cortical tissue from WT and Q93E UBE2A mice showed that UCH-L1 (ubiquitin C-terminal hydrolase 1) is differentially ubiquitinated, suggesting that it is a target of modification by UBE2A. UCH-L1 is a deubiquitinase enzyme capable of processing ubiquitin precursor and catalyzing the hydrolysis of isopeptide bond between ubiquitin and its substrate. It is highly expressed in neurons and its malfunction is associated with neurological disorders such as Parkinson's disease and Alzheimer's, and cancer. We have obtained unprecedented findings that support the interaction between UBE2A and UCH-L1 in vitro and in primary neurons. Also, we have observed the in vitro monoubiquitination of UCH-L1 in the presence of UBE2A. Still, little is known about the function of UCH-L1 ubiquitination and how it is related to neurological diseases. To explore the functional effects of UCH-L1 ubiquitin modification in the cell, we propose a research internship project to be executed in the laboratory of Dr. Gustavo Silva at Duke University. He is an expert in the study of ubiquitination in the control of protein synthesis and degradation. We aim to validate the ability of UBE2A to promote UCH-L1 ubiquitination in cells, to determine the influence of UCH-L1 ubiquitination on its subcellular localization, as well as the effect of its modification on proteolytic pathways or the UCH-L1 hydrolase activity. The results of this project will be essential for the better comprehension of the role of UBE2A-mediated UCH-L1 modification to the development of XLID.