FIG.3.

Subcellular localizations of μ1 in transfected cells examined by fluorescence microscopy. CV-1 cells transfected with pCI-M2(T1L) were fixed at 18 h p.t. and stained as described below for each row of panels. Right panels show colored merges of the different staining patterns, with labels in matching colors. Nuclei were stained with DAPI in each case. Scale bars, 10 μm. (A to C, C′, and F) After fixation, cells were immunostained with the following MAbs as markers for organelles—anti-golgin-97 for Golgi complex (A), anti-LAMP1 for lysosomes (B), anticalnexin for ER (C and C′), and anti-ADRP for lipid droplets (F)—followed by goat anti-mouse IgG conjugated to Alexa 594. Cells were then fixed again and immunostained with anti-μ1 (MAb 4A3) conjugated to Cy2. The area outlined in panel C is enlarged in panel C′ and shows colocalization between calnexin and μ1 (arrowheads). (D) Mitochondria were labeled with MitoTracker CMXros prior to fixation. After fixation, cells were immunostained with anti-μ1 (MAb 4A3) conjugated to Cy2. Arrowheads indicate areas of colocalization between μ1 and mitochondria. (E) After fixation, cells were immunostained with anti-μ1 (MAb 4A3) followed by goat anti-mouse IgG conjugated to Alexa 594. Neutral lipids were then stained with Bodipy 493/503.