Tito Calì

We are interested in studying the molecular mechanisms leading to neurodegeneration. In particular, the role of disease-related proteins on organelle’s physiology and functioning is explored by combining cellular and animal models. Changes in protein subcellular localization and in the connectivity between organelles are increasingly linked to a growing number of diseases, being their impairment an early event in the disease onset. We have developed genetically encoded split-GFP based reporters to follow in vitro and in vivo these important cellular processes.

Multiple proteins linked to neurodegenerative diseases have multiple localizations associated to different functions. How and when shuttling among different subcellular compartments occur is still poorly defined. We have established a novel split-GFP based approach to detect protein translocation within specific submitochondrial compartments upon different cellular stimuli paving the way to the possibility to perform high-throughput screening for direct translocation of proteins of interest within cellular, e.g., submitochondrial, compartments.

Constant bidirectional exchange of nutrients, metabolites, ions, and lipids, as well as protein function and localization at the interface between defined organelles kept in close apposition by defined factors or protein complexes is required to integrate them within specific cellular pathways thus guaranteeing cell fitness. These hubs are therefore crucial, and any deviation is linked to disease conditions such as neurodegeneration, cancer, or diabetes. We have generated the first genetically encoded reporter for in vitro and in vivo monitoring changes in the ER-mitochondria interface, and named it split-GFP-based contact site sensor (SPLICS). The SPLICS family was expanded to explore additional relevant contact sites such as ER-Plasma membrane, ER-peroxisomes, or mitochondria-peroxisomes. Further optimization allowed for the simultaneous detection of contact sites occurring at different membrane interfaces. The development of SPLICS reporters for novel disease-related contact sites and exploration of their behavior in living cells and in model organisms is our focus.

Cieri, Domenico; Vicario, Mattia; Giacomello, Marta; Vallese, Francesca; Filadi, Riccardo; Wagner, Tina; Pozzan, Tullio; Pizzo, Paola; Scorrano, Luca; Brini, Marisa; SPLICS: a split green fluorescent protein-based contact site sensor for narrow and wide heterotypic organelle juxtaposition Cell Death & Differentiation, 25, 6, 1131-1145 2018.                                              

Cieri, Domenico; Vicario, Mattia; Vallese, Francesca; D'Orsi, Beatrice; Berto, Paola; Grinzato, Alessandro; Catoni, Cristina; De Stefani, Diego; Rizzuto, Rosario; Brini, Marisa; Tau localises within mitochondrial sub-compartments and its caspase cleavage affects ER-mitochondria interactions and cellular Ca2+ handling Biochimica et Biophysica Acta (BBA)-Molecular Basis of Disease, 1864, 10, 3247-3256 2018.

Matteucci, Alessandra; Patron, Maria; Vecellio Reane, Denis; Gastaldello, Stefano; Amoroso, Salvatore; Rizzuto, Rosario; Brini, Marisa; Raffaello, Anna; Calì, Tito;  Parkin-dependent regulation of the MCU complex component MICU1, Scientific reports, 8, 1, 1-13, 2018

Calì, Tito; Ottolini, Denis; Vicario, Mattia; Catoni, Cristina; Vallese, Francesca; Cieri, Domenico; Barazzuol, Lucia; Brini, Marisa;          splitGFP technology reveals dose-dependent ER-mitochondria interface modulation by α-Synuclein A53T and A30P mutants       Cells   8, 9, 1072, 2019

Vicario, Mattia; Cieri, Domenico; Vallese, Francesca; Catoni, Cristina; Barazzuol, Lucia; Berto, Paola; Grinzato, Alessandro; Barbieri, Laura; Brini, Marisa; Calì, Tito;  A split-GFP tool reveals differences in the sub-mitochondrial distribution of wt and mutant alpha-synuclein    Cell death & disease 10,     11, 1-16, 2019

Genovese, Ilaria; Giamogante, Flavia; Barazzuol, Lucia; Battista, Theo; Fiorillo, Annarita; Vicario, Mattia; D’Alessandro, Giuseppina; Cipriani, Raffaela; Limatola, Cristina; Rossi, Daniela;   Sorcin is an early marker of neurodegeneration, Ca2+ dysregulation and endoplasmic reticulum stress associated to neurodegenerative diseases Cell death & disease 11, 10, 1-18 2020.

Vallese, Francesca; Catoni, Cristina; Cieri, Domenico; Barazzuol, Lucia; Ramirez, Omar; Calore, Valentina; Bonora, Massimo; Giamogante, Flavia; Pinton, Paolo; Brini, Marisa; An expanded palette of improved SPLICS reporters detects multiple organelle contacts in vitro and in vivo Nature communications 11,   1, 1-15, 2020.

Calì, Tito; Brini, Marisa; Split Green Fluorescent Protein–Based Contact Site Sensor (SPLICS) for Heterotypic Organelle Juxtaposition as Applied to ER–Mitochondria Proximities. Mitochondrial Medicine 363-378, 2021.

Calì, Tito; Brini, Marisa; Quantification of organelle contact sites by split-GFP-based contact site sensors (SPLICS) in living cells. Nature protocols 16, 11, 5287-5308, 2021.

Giamogante, Flavia; Barazzuol, Lucia; Poggio, Elena; Tromboni, Marta; Brini, Marisa; Calì, Tito; Stable Integration of Inducible SPLICS Reporters Enables Spatio-Temporal Analysis of Multiple Organelle Contact Sites upon Modulation of Cholesterol Traffic Cells 11, 10, 1643 2022.