Analysis of Clone A1-L4 gene expression. Protein expression from Clone A1-L4 was analysed by fluorescence microscopy. 293TETOFF (a, b, e & f), Clone A1 (c, d, g & h) and Clone A1-L4 cells (i-p) were grown in the presence (a-d & i-l) or absence (e-h & m-p) of Dox for 3 days with daily media changes. Cells were fixed and stained for L4-100K (red, i, j, m & n) or FLAG-tagged L4-33K (red, a-h, k, l, o & p) and nuclear DNA (DAPI, blue) and visualised using a Leica SP2 confocal microscope. GFP autofluorescence was also imaged (green). Images b, d, f, h, j, l, n & p are overlays in Leica software of the L4-100K or L4-33KFLAG images with GFP and DAPI images, collected sequentially to avoid cross-talk between fluors.