FIGURE 1: Images of C. elegans nematode used as a model to study aging and longevity.(A) Light microscopy and (B) fluorescence microscopy images of transgenic C. elegans strain CGUIS-1 expressing the nucleolar protein fibrillarin 1 (FIB-1) coupled to green fluorescent protein (GFP). FIB-1 is a marker of nucleolus size that negatively correlates with longevity across taxa [161], making the CGUIS-1 strain useful for screening natural products that may extend lifespan. In B, GFP auto-fluorescence is induced by ultraviolet light. The images are unpublished observations made by the authors.

161. Tiku V, Jain C, Raz Y, Nakamura S, Heestand B, Liu W, Spath M, Suchiman HED, Muller RU, Slagboom PE, Partridge L, Antebi A (2017). Small nucleoli are a cellular hallmark of longevity. Nat Commun 8: 16083. 10.1038/ncomms16083