Figure 7: TOM1L1 is recruited by TOLLIP to RAB-7/MT1-MMP endosomes for MT1-MMP trafficking.
From: TOM1L1 drives membrane delivery of MT1-MMP to promote ERBB2-induced breast cancer cell invasion
(a) Co-localization of TOLLIP and RAB-7. About 48 h after GFP–RAB-7 and HA–TOLLIP transfection, 3T3-neu cells infected with viruses expressing the indicated constructs were seeded on gelatin-coated coverslips for 3 h and immunolabelled using an anti-HA antibody. ‘Zoom’ panels show higher magnification of the boxed areas. Note the relocalization of TOLLIP/RAB-7 co-localization at the cell periphery when TOM1L1 is expressed. Scale bar, 20 μm. (b) Endosomal TOM1L1 recruitment by TOLLIP. 3T3-neu cells were transfected with GFP–TOM1L1 or GFP–ΔGAT alone or with HA–TOLLIP. About 48 h after transfection cells were seeded on gelatin-coated glass bottom dishes to visualize TOM1L1 localization. ‘Zoom‘ panels show higher magnification of the boxed areas. Scale bar, 20 μm. (c) Endosomal co-localization of TOM1L1, TOLLIP and MT1-MMP. About 48 h after GFP–TOM1L1/ΔGAT, HA–TOLLIP and mCherry MT1-MMP transfection, 3T3-neu cells were plated on gelatin-coated coverslips for 3 h then immunolabelled with an anti-HA antibody to visualize co-localization. Insets show higher magnification of the boxed areas. Scale bar, 20 μm. (d) Co-localization of MT1-MMP, RAB-7 and TOLLIP in BT-474 cells. BT-474 cells were transfected with mCherry–MT1-MMP, GFP–Rab-7 and HA–TOLLIP. About 48 h after transfection, cells were plated on gelatin-coated coverslips and imaged by confocal orthogonal (x/z) imaging. Note the basal co-localization of mCherry–MT1-MMP, GFP–RAB-7 and HA–TOLLIP (arrowheads). Scale bar, 10 μm.
