Suchergebnisse

Plasma membrane tension regulates many key cellular processes. It is modulated by, and can modulate, membrane trafficking. However, the cellular pathway(s) involved in this interplay is poorly understood. Here we find that, among a number of endocytic processes operating simultaneously at the cell surface, a dynamin independent pathway, the CLIC/GEEC (CG) pathway, is rapidly and specifically upregulated upon a sudden reduction of tension. Moreover, inhibition (activation) of the CG pathway results in lower (higher) membrane tension. However, alteration in membrane tension does not directly modulate CG endocytosis. This requires vinculin, a mechano-transducer recruited to focal adhesion in adherent cells. Vinculin acts by controlling the levels of a key regulator of the CG pathway, GBF1, at the plasma membrane. Thus, the CG pathway directly regulates membrane tension and is in turn controlled via a mechano-chemical feedback inhibition, potentially leading to homeostatic regulation of membrane tension in adherent cells. ; We thank Pietro De Camilli (Yale University, USA) for conditional Dynamin triple knockout cell line, Daniel Rosel (Charles University, Prague) for vinculin-null cell line, Darius V. Koster for the caveolin-null cell line, David J. Stephens (University of Bristol, UK) for an initial gift of LG186, Philippe Benaroch (Institut Curie, Paris) for AP2 shRNA, Clare M. Waterman (NIH, USA) for vinculin constructs, Feroz M.H. Musthafa (CCAMP, Bangalore) and G.V. Soni (RRI, Bangalore) for help with preparation of PDMS membrane. We would like to thank Manoj Mathew and central imaging and flow cytometry facility (CIFF, NCBS) for help with imaging, Dev Kumar (Mech. Workshop) for making components for stretch-relax apparatus and imaging, Dr. Anusuya Banerjee for help with illustrations, K. Joseph Mathew for final cartoon and thank members of P.P., X.T. and P.R-C. laboratories for hosting and helping J.J.T. with day-to-day experiments. X.T. acknowledges support from the Spanish Ministry of Economy and Competitiveness (BFU2015-65074-P), the Generalitat de Catalunya (2014-SGR-927) and the European Research Council (ERC-2013-CoG-616480). This work was supported by the Spanish Ministry of Economy and Competitiveness (BFU2016-79916-P to P.R.-C.), the European Commission (H2020-FETPROACT-01-2016-731957 to X.T. and P.R.-C.) and Obra Social `La Caixa'. A.E.-A. acknowledges support by Juan de la Cierva Fellowship from Spanish Ministry of Economy and Competitiveness (IJCI-2014-19156). This study was also supported by grants SAF2014-51876-R from Spanish Ministry of Economy and Competitiveness (MINECO) and co-funded by FEDER funds to M.A.d.P., and 674/C/2013 from Fundacio La Marato de TV3 to P.R.-C. and M.A.d.P. R.G.P. was supported by the National Health and Medical Research Council (NHMRC) of Australia (program grant, APP1037320 and Senior Principal Research Fellowship, 569452), and the Australian Research Council Centre of Excellence (CE140100036). We acknowledge the Australian Microscopy \& Microanalysis Research Facility at the Center for Microscopy and Microanalysis at The University of Queensland. J. J.T. acknowledges pre-doctoral fellowship from Council for Scientific and Industrial Research (CSIR), Government of India. S.M. would like to acknowledge J.C. Bose Fellowship from DST, Government of India, and Wellcome Trust-DBT Margdarshi fellowship (IA/M/15/1/502018). ; Sí