From the "bottom-up" we are reconstituting cellular phenomena in eukaryotic cytoplasmic extract from frog eggs, with <ahref="https://mitchison.hms.harvard.edu/">Timothy Mitchison</a> and <ahref="http://www.fakhrilab.com/">Nikta Fakhri</a>. For example, we are investigating geometrical and mechanical aspects of intracellular scaffolds such as microtubules, actin, and endoplasmic reticulum. I enjoy thinking about these cytoskeletal scaffolds as “LEGO soup,” composed of many different molecules that are constantly using energy to self-organize, assembling and disassembling to make different structures that can do different jobs at different times.