Deficient Endoplasmic Reticulum-Mitochondrial Phosphatidylserine Transfer Causes Liver Disease - UTU Research Portal

A1 Refereed original research article in a scientific journal

Deficient Endoplasmic Reticulum-Mitochondrial Phosphatidylserine Transfer Causes Liver Disease

Authors: María Isabel Hernández-Alvarez, David Sebastián, Sara Vives, Saška Ivanova, Paola Bartoccioni, Pamela Kakimoto, Natalia Plana, Sónia R. Veiga, Vanessa Hernández, Nuno Vasconcelos, Gopal Peddinti, Anna Adrover, Mariona Jové, Reinald Pamplona, Isabel Gordaliza-Alaguero, Enrique Calvo, Noemí Cabré, Rui Castro, Antonija Kuzmanic, Marie Boutant, David Sala, Tuulia Hyotylainen, Matej Orešič, Joana Fort, Ekaitz Errasti-Murugarren, Cecilia M.P. Rodrígues, Modesto Orozco, Jorge Joven, Carles Cantó, Manuel Palacin, Sonia Fernández-Veledo, Joan Vendrell, Antonio Zorzano

Publisher: CELL PRESS

Publication year: 2019

Journal: Cell

Journal name in source: CELL

Journal acronym: CELL

Volume: 177

Issue: 4

First page : 881

Last page: 895

Number of pages: 32

ISSN: 0092-8674

eISSN: 1097-4172

DOI: https://doi.org/10.1016/j.cell.2019.04.010

Abstract

Non-alcoholic fatty liver is the most common liver disease worldwide. Here, we show that the mitochondria' protein mitofusin 2 (Mfn2) protects against liver disease. Reduced Mfn2 expression was detected in liver biopsies from patients with nonalcoholic steatohepatitis (NASH). Moreover, reduced Mfn2 levels were detected in mouse models of steatosis or NASH, and its re-expression in a NASH mouse model ameliorated the disease. Liver-specific ablation of Mfn2 in mice provoked inflammation, triglyceride accumulation, fibrosis, and liver cancer. We demonstrate that Mfn2 binds phosphatidylserine (PS) and can specifically extract PS into membrane domains, favoring PS transfer to mitochondria and mitochondria' phosphatidylethanolamine (PE) synthesis. Consequently, hepatic Mfn2 deficiency reduces PS transfer and phospholipid synthesis, leading to endoplasmic reticulum (ER) stress and the development of a NASH-like phenotype and liver cancer. Ablation of Mfn2 in liver reveals that disruption of ER-mitochondrial PS transfer is a new mechanism involved in the development of liver disease.