Welcome to the De Cesare Laboratory!
At the De Cesare Laboratory, we are dedicated to unravelling the biological role of non-canonical ubiquitylation.
Ubiquitylation, an eminent Post-Translational Modification (PTM), has long been associated with lysine residues. However, in the last years there has been a growing number of compelling evidence that challenges this conventional view, showcasing the remarkable ability of multiple ubiquitin enzymes to attach and remove ubiquitin from residues beyond lysine. Our research focuses on understanding the fascinating realm of non-canonical ubiquitylation, where ubiquitin can be attached to amino acids such as serine, threonine, and various other biomolecules, including sugars and bacterial lipopolysaccharides. This expansion of ubiquitylation into non-canonical territories opens up new avenues for exploration and redefines our understanding of this fundamental PTM.
Understanding the biological function of non-canonical E2s
Several classes of enzymes oversee the attachment of ubiquitin to its substrates: a single E1 activating enzyme makes ubiquitin chemically susceptible prior to the following stages of conjugation and ligation, respectively mediated by E2 conjugating enzymes (E2s) and E3 ligases (E3s). Around 40 E2s and more than 600 E3s are encoded in the human genome, and their combinatorial and cooperative behaviour dictates the tight specificity necessary for the regulation of thousands of substrates. The removal of ubiquitin is orchestrated by a network of about 100 deubiquitylating enzymes (DUBs). Many cellular processes are tightly controlled by ubiquitylation, which is essential for maintaining cellular homeostasis. Because of the fundamental role(s) of ubiquitylation, there is an interest in better understanding the function and specificity of the ubiquitin machinery and to develop drugs and treatment regimens that can modify its activity and/or specificity.
Central to the attachment of ubiquitin to its substrates are the E2 conjugating enzymes (E2s). In recent breakthroughs, we have identified a family of non-canonical E2s, namely UBE2Q1, UBE2Q2, and UBE2QL1, with the extraordinary ability to attach ubiquitin to serine, threonine, and other hydroxyl-containing biomolecules (see Selected publication 1). These findings have shed light on the vital role played by non-canonical E2s in expanding the reach of ubiquitylation. Intriguingly, the absence of UBE2Q1 generates a profound impact, leaving UBE2Q1 Knock Out mice facing infertility due to embryo implantation failure and posing the following research questions. What crucial biological role(s) does UBE2Q1 play during embryo attachment? What are the substrates and the biological pathway(s) these non-canonical E2s engage with?
One of our primary objectives is to uncover the cellular mechanisms and functions governed by these unique E2 enzymes. To achieve this, we employ a comprehensive range of cutting-edge techniques, including Matrix-Assisted Laser Desorption/Ionization-Time of Flight mass spectrometry (MALDI-TOF MS) and Liquid Chromatography mass spectrometry (LC-MS) besides advanced structural and molecular biology tools.
Developing MALDI-TOF MS tools for interrogating ubiquitin enzymes
In addition to our research on non-canonical ubiquitylation, we are committed to advancing the field of MALDI-TOF MS-based tools. Our laboratory pioneers the development, expansion, and refinement of MALDI-TOF MS platforms, harnessing their versatility, high-throughput capabilities, and user-friendly nature (See Selected Publication 2-5). Our focus lies in probing ubiquitin enzyme activities, substrate preferences, and cooperative behaviours, pushing the boundaries of our understanding of ubiquitin and ubiquitin-like enzymes.
Collaboration lies at the heart of our scientific endeavours. We actively foster collaborations with both national and international research groups and companies, forging interdisciplinary partnerships that enhance our research capabilities and accelerate scientific progress.
Together We Thrive
In De Cesare lab we embrace and celebrate the unique perspective of every individual within our group. We aim to create opportunities for everyone to thrive, regardless of their race, religion, or gender identity, and to support every lab member in their career path and scientific growth.
If you wish to join our mission to decipher the enigmatic functions of non-canonical ubiquitylation or become an expert in High-throughput MALDI-TOF MS, please get in touch!