To examine the time course of stress granule assembly, we exposed human osteosarcoma cells (U-2 OS) expressing a GFP-G3BP1 fusion protein (Kedersha et al., 2008; Ohn et al., 2008) to NaAsO2 and collected images over time using a spinning disc confocal microscope. Here, G3BP1 is linked to osteosarcoma.