Dissecting the actin cortex density and membrane-cortex distance in living cells by super-resolution microscopy

摘要: Nanoscale spacing between the plasma membrane and underlying cortical actin cytoskeleton profoundly modulates cellular morphology, mechanics, function. Measuring this distance has been a key challenge in cell biology. Current methods for dissecting nanoscale either limit themselves to complex survey design using fixed samples or rely on diffraction-limited fluorescence imaging whose spatial resolution is insufficient quantify distances nanoscale. Using dual-color super-resolution STED (stimulated-emission-depletion) microscopy, we here overcome accurately measure density distribution of cortex live Jurkat T-cells. We found an asymmetric with mean width 230 (+105/−125) nm. The measured maximum peaks were bi-modally distributed values 50 ± 15 nm 120 40 nm, respectively. Taken together finite cortex, our results suggest that some regions closer than 10 20 others.