Journal: bioRxiv
Article Title: EMT activates ER-to-Golgi trafficking through upregulation of REEP2 to promote lung cancer progression
doi: 10.1101/2025.11.12.688098
Figure Lengend Snippet: (A) Schematic illustration of the retention using selective hooks (RUSH) system. The cells were co-transfected with the reporter protein (CD-MPR), which is fused to the streptavidin-binding peptide (SBP) and GFP, and a second protein with a C-terminal ER retention signal (Lys-Asp-Glu-Leu; KDEL) fusing with streptavidin as a hook. The interaction of CD-MPR with the hook protein retains CD-MPR in the ER compartment and biotin administration releases the CD-MPR-GFP reporter from the ER and transfers it to the Golgi. (B) Schematic of VSV-G assay. The cells were transfected with vectors that express an EGFP-tagged temperature-sensitive mutant VSV-G (EGFP-VSV-G [ts045]) that is transported from the ER to the plasma membrane via the Golgi. At designated time points after switching cells to temperatures that cause VSV-G accumulation (40°C) and release (32°C) from the ER, cells were fixed and exofacial VSV-G was detected in non-permeabilized cells by staining with anti-VSV-G monoclonal antibody. The VSV-G trafficking to the plasma membrane is determined by the ratio of exofacial (surface) VSV-G fluorescence signal to the EGFP signal intensity. (C) Confocal micrographs of cells co-stained with anti-SEC16A (green) and anti-GM130 (red) antibodies. DAPI (blue). Scale bar: 5 μm. The scatter plots quantify Golgi-localized SEC16A per cell (dot) based on % of total SEC16A that co-localizes with Golgi (GM130 channel) (n = 15 cells per group) in H1299 cells treated with vehicle control (Veh) or 5 µM thapsigargin (Tg) for 1 h. (D) Confocal micrographs of EGFP-VSV-G-transfected cells taken 1 h after transfer to permissive temperature. Scale bar, 5 μm. The scatter plot represents the ratio of surface VSV-G to EGFP-VSV-G in each cell (dot) (n = 15 cells per group) in H1299 cells treated with vehicle control (Veh) or 5 µM thapsigargin (Tg) for 1 h. Results represent means ± SEM. P values were determined using two-tailed Student’s t-test.
Article Snippet: We purchased fetal bovine serum (FBS), live-cell imaging solution, phosphate-buffered saline (PBS), RPMI-1640, Trypsin-EDTA (0.25%), Alexa Fluor-tagged secondary antibodies, paraformaldehyde, bovine serum albumin (BSA), DAPI and Triton X-100, High-Capacity cDNA Reverse Transcription Kit, PowerUpTM SYBRTM Green Master Mix, and protease/phosphatase inhibitor cocktail from Thermo Fisher Scientific; Doxycycline (#D9891) from MilliporeSigma; Bronchial Epithelial Cell Growth Medium BulletKit from Lonza; jetPRIME transfection reagent from Polyplus Transfection; Transwell and Matrigel-coated Boyden chambers from BD Biosciences; Glass-bottom dishes and multiwell plates from MatTek; 10X Cell lysis buffer from Cell Signaling Technologies; 2X cell lysis buffer (#1610737) from Bio-Rad; CCK-8 (#K1018) from APExBIO; RNeasy Plus Mini Kit (#74136), and AllStars Negative Control siRNA (#1027281) from QIAGEN; Pre-miRTM miRNA Precursor Negative Control (miR-NC) (#AM17110); human miR-183a mimics (#PM12303) and human miR-193 mimics (#PM11786) from Thermo Fisher Scientific; human REEP2 siRNA #2 (#J-021201-18), and #4 (J-021201-20) from Horizon; primary antibodies against β-actin (#4967), ZEB1 (#3396) from Cell Signaling Technologies, REEP2 (#Ab191410) from Abcam, SEC16A (#20025-1-AP) from Proteintech, VSV-G (#EB0012) from Kerafast; Alexa Fluor 555 Mouse anti-GM130 (#560066) from BD Biosciences; REEP2-GFP (#RC202507L4) from Origene; SEC24D-mCherry (#32677), Golgi-pmTurquoise2 (#36205), mCherry-Golgi (#55052) and CD-MPR-GFP-RUSH (#202797) from Addgene; 3’-UTR luciferase reporters of REEP2 (#38786081) from Applied Biological Materials; pCI-Neo Renilla luciferase reporter (Basic) (#E1841) and pGL3 Basic Firefly luciferase control reporter (#E1751) from Promega; All-in-One miRNA qRT-PCR Detection Kit 2.0 (#QP115) from GeneCopoeia.
Techniques: Transfection, Binding Assay, Mutagenesis, Clinical Proteomics, Membrane, Staining, Fluorescence, Control, Two Tailed Test