Bioinformatics Institute 1 article published in JoVE Biology Quantitative Localization of a Golgi Protein by Imaging Its Center of Fluorescence Mass Hieng Chiong Tie1, Bing Chen1, Xiuping Sun1, Li Cheng2,3, Lei Lu1 1School of Biological Sciences, Nanyang Technological University, 2Bioinformatics Institute, 3School of Computing, National University of Singapore The precise localization of Golgi residents is essential for understanding the cellular functions of the Golgi. However, conventional optical microscopy is unable to resolve the sub-Golgi structure. Here we describe the protocol for a conventional microscopy based super-resolution method to quantitatively determine the sub-Golgi localization of a protein.