TY - JOUR A1 - Dejonghe, Wim A1 - Kuenen, Sabine A1 - Mylle, Evelien A1 - Vasileva, Mina A1 - Keech, Olivier A1 - Viotti, Corrado A1 - Swerts, Jef A1 - Fendrych, Matyas A1 - Ortiz-Morea, Fausto Andres A1 - Mishev, Kiril A1 - Delang, Simon A1 - Scholl, Stefan A1 - Zarza, Xavier A1 - Heilmann, Mareike A1 - Kourelis, Jiorgos A1 - Kasprowicz, Jaroslaw A1 - Nguyen, Le Son Long A1 - Drozdzecki, Andrzej A1 - Van Houtte, Isabelle A1 - Szatmari, Anna-Maria A1 - Majda, Mateusz A1 - Baisa, Gary A1 - Bednarek, Sebastian York A1 - Robert, Stephanie A1 - Audenaert, Dominique A1 - Testerink, Christa A1 - Munnik, Teun A1 - Van Damme, Daniel A1 - Heilmann, Ingo A1 - Schumacher, Karin A1 - Winne, Johan A1 - Friml, Jiri A1 - Verstreken, Patrik A1 - Russinova, Eugenia T1 - Mitochondrial uncouplers inhibit clathrin-mediated endocytosis largely through cytoplasmic acidification JF - Nature Communications N2 - ATP production requires the establishment of an electrochemical proton gradient across the inner mitochondrial membrane. Mitochondrial uncouplers dissipate this proton gradient and disrupt numerous cellular processes, including vesicular trafficking, mainly through energy depletion. Here we show that Endosidin9 (ES9), a novel mitochondrial uncoupler, is a potent inhibitor of clathrin-mediated endocytosis (CME) in different systems and that ES9 induces inhibition of CME not because of its effect on cellular ATP, but rather due to its protonophore activity that leads to cytoplasm acidification. We show that the known tyrosine kinase inhibitor tyrphostinA23, which is routinely used to block CME, displays similar properties, thus questioning its use as a specific inhibitor of cargo recognition by the AP-2 adaptor complex via tyrosine motif-based endocytosis signals. Furthermore, we show that cytoplasm acidification dramatically affects the dynamics and recruitment of clathrin and associated adaptors, and leads to reduction of phosphatidylinositol 4,5-biphosphate from the plasma membrane. Y1 - 2016 U6 - https://doi.org/10.1038/ncomms11710 SN - 2041-1723 VL - 7 SP - 1959 EP - 1968 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Langenhan, Jennifer A1 - Jaeger, Carsten A1 - Baum, Katharina A1 - Simon, Mareike A1 - Lisec, Jan T1 - A flexible tool to correct superimposed mass isotopologue distributions in GC-APCI-MS flux experiments JF - Metabolites N2 - The investigation of metabolic fluxes and metabolite distributions within cells by means of tracer molecules is a valuable tool to unravel the complexity of biological systems. Technological advances in mass spectrometry (MS) technology such as atmospheric pressure chemical ionization (APCI) coupled with high resolution (HR), not only allows for highly sensitive analyses but also broadens the usefulness of tracer-based experiments, as interesting signals can be annotated de novo when not yet present in a compound library. However, several effects in the APCI ion source, i.e., fragmentation and rearrangement, lead to superimposed mass isotopologue distributions (MID) within the mass spectra, which need to be corrected during data evaluation as they will impair enrichment calculation otherwise. Here, we present and evaluate a novel software tool to automatically perform such corrections. We discuss the different effects, explain the implemented algorithm, and show its application on several experimental datasets. This adjustable tool is available as an R package from CRAN. KW - mass isotopologue distribution KW - enrichment calculation KW - flux KW - experiments KW - atmospheric pressure chemical ionization KW - R package KW - CorMID Y1 - 2022 U6 - https://doi.org/10.3390/metabo12050408 SN - 2218-1989 VL - 12 IS - 5 PB - MDPI CY - Basel ER -