Quantitative Analysis of Photobodies.

Photobodies are membraneless subnuclear organelles that contain the red and far-red photoreceptors, phytochromes. Photobody biogenesis has been postulated to play important roles in early light signaling events. The size and number of photobodies are highly dynamic in response to the quality and quantity of light and correlated tightly with phytochrome-mediated seedling morphogenesis. Here, we provide a detailed protocol for characterization of the three-dimensional morphology of photobodies, including sample preparation, fluorescence microscopy, and image analysis. Although this method was developed initially for characterizing photobodies, it can be adopted to analyze other membraneless or membrane-bound subcellular organelles.