COS 7 cell expressing Organelle LightsTM Golgi-GFP (Invitrogen)consisting of the human Golgi-resident enzyme N- acetylgalactosaminyltransferase 2. Images were collected with a 63X 1.4 NA Plan-Apochromat oil objective on a Zeiss LSM510 META (Carl Zeiss, Thornwood, NY) using 488 nm excitation, HFT 488 dichroic, and LP505 emission filter. Image size is 512 x 512, pixel size is 0.1 µm x 0.1 µm and pixel time was set to 1.6 µsec. Detector pinhole was set to collect 18 ~0.5 µm slices at 0.5 µm intervals