Figure 1. 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 The images are unpublished observations made by the authors.