Journal: Nature Communications
Article Title: Ubiquitination by HRD1 is essential for TLR3 trafficking and its innate immune signaling
doi: 10.1038/s41467-025-67219-0
Figure Lengend Snippet: a – f Confocal microscopic images of TLR3 co-stained with DAPI and ER marker KDEL ( a ), trans-Golgi network marker TGN38 ( b ) and lysosome marker LAMP1 ( c ) in WT and Hrd1 −/− RAW 264.7 cells with or without poly(I:C) (50 µg/ml) treatment. Quantitation of the fraction of TLR3 in the ER ( d , from left to right, n = 60, 58, 60, 60, 60, 60), trans-Golgi network ( e , n = 60 for all groups), and lysosomes ( f , n = 60 for all groups) in these macrophages were shown. Mander’s overlap coefficient is used for measurement of colocalization. g – j Confocal microscopic images of TLR3-Flag co-stained with DAPI and ER marker Calnexin ( g ), Golgi marker GM130 ( h ), early endosome marker Rab5 ( i ) and late endosome marker Rab7 ( j ) in WT and Hrd1 −/− HEK293T cells transfected with TLR3-Flag plasmid and with or without poly(I:C) treatment. k – m Immunoblot analysis of full-length (FL) and cleaved TLR3 (CL) in WT and Hrd1 −/− HEK293T cells transfected with TLR3-Flag plasmid and treated with 50 μg/ml poly(I:C) for 12 h ( k ), LS-102 (5 μM) for 8 h ( l ), and with Endo H or PNGase F ( m ). Arrow, Endo H-sensitive; Red box, Endo H-resistant. n Immunoblot analysis of indicated proteins following the isolation of the ER, Golgi and endosomes from WT and Hrd1 −/− HEK293T cells transfected with TLR3-Flag for 24 h, followed by 50 µg/ml poly(I:C) stimulation for 1 h. Relative quantitation of indicated TLR3 bands shown below the blot. o – q Immunoblot analysis of indicated proteins following immunoprecipitation of TLR3-Flag in the lysates of HEK293T cells transfected with TLR3-Flag, HRD1-myc (WT, C2A, and ΔRING), and HRS-V5 ( o ), or TGS101-V5 ( p ), or VPS36-V5 ( q ). C2A, HRD1-dead variant; ΔRING, RING domain-deleted truncate. Quantitation of the protein level is shown below the blot. All confocal image and blot data were representative of at least three independent repeats ( a – q ). Values represent mean ± SEM, by unpaired, two-tailed, Student’s t -test ( d – f ). Source data are provided as a Source Data file.
Article Snippet: Primary antibodies for immunofluorescent staining included: TLR3 (Proteintech 17766-1-AP, 1: 200), Calnexin (Proteintech 10427-2-AP, 1: 200), GM130 (Proteintech 11308-1-AP, 1:1000), Rab5 (Cell Signaling C8B1; 1: 200), Rab7 (Cell Signaling D95F2; 1: 200), KDEL (Novus Biologicals NBP1-97469, 1:200), TGN38 (Santa Cruz sc-166594,1:200), LAMP1 (Proteintech 65050-1-Ig, 1:1000), Flag (Sigma F1804, 1: 200).
Techniques: Staining, Marker, Quantitation Assay, Transfection, Plasmid Preparation, Western Blot, Isolation, Immunoprecipitation, Variant Assay, Two Tailed Test