Reticulon 3–dependent ER-PM contact sites control EGFR nonclathrin endocytosis

Abstract

The integration of endocytic routes is critical to regulate receptor signaling. A non-clathrin endocytic pathway (NCE) of the epidermal growth factor receptor (EGFR) is activated at high ligand concentrations and targets receptors to degradation, attenuating signaling. Here we performed an unbiased molecular characterization of EGFR-NCE. We identified NCE-specific regulators, including the endoplasmic reticulum (ER)-resident protein reticulon-3 (RTN3), and a specific cargo, CD147. RTN3 was critical for EGFR/CD147-NCE, promoting the creation of plasma membrane (PM)-ER contact sites that were required for the formation/maturation of NCE invaginations. Ca 2+ release at these sites, triggered by IP3-dependent activation of ER Ca 2+ channels, was needed for the completion of EGFR internalization. Thus, we identified a mechanism of EGFR endocytosis that relies on ER-PM contact sites and local Ca 2+ signaling. This manuscript has been accepted for publication in Science and it is under embargo until the publication date. This version has not undergone final editing. Please refer to the complete version of record at http://www.sciencemag.org/. The manuscript may not be reproduced or used in any manner that does not fall within the fair use provisions of the Copyright Act without the prior, written permission of AAAS.Correspondence

N‐glycosylation by N‐acetylglucosaminyltransferase V enhances the interaction of CD147/basigin with integrin β1 and promotes HCC metastasis

“…As the levels of CD147/basigin glycosylation in HCC were unknown, we assessed the levels of β1,6‐branched glycans in HCC tissue and cancer cell lines (Figure B and supplementary material, Figure S1) and found high levels on the plasma membrane. Furthermore, our PLA results (Figure B) confirmed that CD147/basigin was highly glycosylated with β1,6‐branching in HCC, which is consistent with previous findings . To determine the correlation with prognostic features in HCC, 51 patients with HCC were analyzed; only Barcelona clinic liver cancer (BCLC) stage was related to the level of CD147/basigin‐β1,6‐branched glycans (Table , p = 0.016).…”

Emerging functions of the EGFR in cancer

“…EGFR-CME is active at all ligand concentrations in all type of cells (Carpentier et al, 1982;Goh et al, 2010;Hanover et al, 1984;Jiang et al, 2003;Sigismund et al, 2008;Sorkin and Carpenter, 1993). Conversely, the EGFR-NCE pathwaysdespite their molecular and morphological differencesare generally activated at higher, but still physiologically relevant, EGF doses (≥ 10 ngÁmL À1 ) and their significance is cell context dependent (Boucrot et al, 2015;Caldieri et al, 2017;Orth et al, 2006;also reviewed in Barbieri et al, 2016).…”

The axonal endoplasmic reticulum: One organelle—many functions in development, maintenance, and plasticity

“…Different ER‐plasma membrane contacts control cell signaling. For example, clathrin‐independent epidermal growth factor (EGF)‐induced endocytosis of EGF receptor (EGFR) requires ER‐plasma membrane contacts mediated by reticulon 3 on HeLa cells (Caldieri et al, ). Additionally, ER‐plasma membrane contacts may act as a sink to remove the excess of inositol 1,4,5‐trisphosphate (IP 3 ) and diacyl‐glycerol (DAG), accumulated in the plasma membrane after phospholipase C (PLC) hydrolysis of phosphatidylinositol‐4,5‐bi‐phosphate PI(4,5)P 2 (Saheki et al, ).…”