Single Molecule Imaging in Live C-elegans using Complementation-activated Light Microscopy (CALM)

In recent years, single-molecule (SM) fluorescence microscopy techniques have been applied to the study of biomolecules in cultured cells. Extending these techniques to live animal imaging could open new avenues to examine the nanoscale behaviors of signaling molecules under homeostatic control within live tissues and during various developmental or pathogenic stages. SM fluorescence imaging in intact adult animals remains highly challenging, despite previous efforts to track individual biomolecules in embryos and early larval stages of zebrafish and C. elegans nematodes. This application note demonstrates the imaging of fluorescent biomolecules at the single molecule level in living adult animals using far-field fluorescence microscopy and CALM.