Motility of normal and mutant cells expressing Rac proteins analyzed by videomicroscopy.
Transduced patient and normal myeloid cells were allowed to adhere to glass coverslips before they were loaded into a Zigmond chamber with a 0 to 10−5 mol/L chemotactic gradient of fMLP. The speed of GFP-positive cells, identified using epifluorescence, was analyzed from video frames digitized at 1-minute intervals. (A) Histogram of speeds of control transduced normal and patient cells (normal/MIEG3, patient/MIEG3), and patient cells transduced with WT murine Rac2 (patient/MIEG3FR2). Data shown are from 1 of 2 experiments with similar results. (B) Histogram of speeds of normal cells expressing EGFP alone (MIEG3), D57N mutant Rac2 (HR2MU), or WT Rac2 (HR2WT). Data shown represent 1 of 3 experiments with similar results.