The Mito tracking peptide targets proteins to the mitochondria. NIH 3T3 cells were transiently transfected with vectors expressing either the N-terminus of Angiomotin fused to a C-terminal ECFP (top panel) or the same protein fused to a C-terminal ECFP plus a mitochondrial tracking peptide (ECFP-mito) (bottom panel). The cells were fixed and stained with anti-ECFP (green colour in merge) that recognizes the fusion construct or anti-Cytochrome C (red colour in merge) to mark the mitochondrial membrane. DNA is stained with Hoescht (blue colour in merge). The bottom right image on both panels is a composite of all three stainings. Note that only transfected cells will display ECFP staining. Abbreviations – mito – Mito tracker, Cyt C – Cytochrome C, ECFP – enhanced cyano fluorescent protein.