Fiolka, R. et al. Proc. Natl. Acad. Sci. USA 109, 5166–5169 (2012).

Structured illumination is a resolution-doubling alternative to higher-resolution super-resolution methods and can image larger areas at greater speed with lower irradiation intensities. But whereas other super-resolution methods have been used for two-color time-lapse imaging of living cells, imaging of more than one color by structured-illumination microscopy has been limited to fixed cells. Replacement of a mechanically translated diffraction grating with nonmechanical light modulators recently allowed structured-illumination microscopy to achieve fast, time-lapse imaging of living cells, but the wavelength dependence of the method precluded imaging more than one color. Fiolka et al. adapted this setup for wavelength-dependent adjustment of the illumination. This allowed them to image an entire living cell in three dimensions and two colors at 22 seconds per frame. Reducing the imaged volume to a 1.25-micrometer-thick slice of the cell increased the speed to 8.5 seconds per frame.