Figure 3
![Figure 3](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2F2191-219X-4-9/MediaObjects/13550_2013_Article_192_Fig3_HTML.jpg)
Subcellular localization of exendin-4 in cultivated tumor β-cells of Rip1Tag2 mice 2 h after injection. Tumor beta-cells were incubated with FAM-exendin-4 (A, green), anti-Lamp-2 (B, red, an anti-lysosome antibody), and nuclear DAPI stain (C, blue). Fluorescein-exendin-4 was internalized into the cytoplasm and into the nuclei of tumor beta-cells. However, there was only a minimal co-localization of FAM-exendin and Lamp-2 (D, merged picture).