bioRxiv preprint doi: https://doi.org/10.1101/625913; this version posted July 12, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 Dynamic trafficking and turnover of Jam-C is 2 essential for endothelial cell migration 3 4 Katja B. Kostelnik1¥, Amy Barker1¥, Christopher Schultz1, Vinothini Rajeeve2, Ian 5 J. White3, Michel Aurrand-Lions4, Sussan Nourshargh1, Pedro Cutillas2 and 6 Thomas D. Nightingale1◊ 7 1. Centre for Microvascular Research, William Harvey Research Institute, Barts and the London School of 8 Medicine and Dentistry, Queen Mary University of London, UK. 9 2. Cell Signalling & Proteomics Group, Barts Cancer Institute, Queen Mary University of London, London, UK. 10 3. MRC Laboratory of Molecular Cell Biology, University College London, London, UK. 11 4. Aix Marseille University, CNRS, INSERM, Institut Paoli-Calmettes, CRCM, Marseille, France 12 ¥ These authors contributed equally 13 ◊ Author for correspondence:
[email protected] 14 15 Abstract 16 Junctional complexes between endothelial cells form a dynamic barrier that hinder passive 17 diffusion of blood constituents into interstitial tissues. Re-modelling of junctions is an 18 essential process during leukocyte trafficking, vascular permeability and angiogenesis. 19 However, for many junctional proteins the mechanisms of junctional remodelling have yet to 20 be determined. Here we used receptor mutagenesis, HRP and APEX-2 proximity labelling, 21 alongside light and electron microscopy, to map the intracellular trafficking routes of 22 junctional adhesion molecule-C (Jam-C). We found that Jam-C co-traffics with receptors 23 associated with changes in permeability, such as VE-Cadherin, NRP-1 and 2, but not with 24 junctional proteins associated with the transmigration of leukocytes.