“…Cytoophidia, or "cellular snakes", are evolutionary conserved MLOs found in the cells of many species in all three domains of life and represent an interesting case of metabolic regulation via enzyme filamentation and resulting compartmentalization [27,28]. In the first paper of this miniseries, Yi-Fan Fang, Yi-Lan Li, Xiao-Ming Li, and Ji-Long Liu used fluorescence recovery after photobleaching (FRAP) to study the dynamic characteristics of cytoophidium in human cell lines and also utilized stimulated emission depletion (STED) microscopy to analyze the super-resolution structure of these cellular snakes [25]. This analysis revealed that cytoophidia are dynamic and reticular, with the reticular structure of CTPS cytoophidia potentially providing space for other components [25], such as inosine monophosphate dehydrogenase (IMPDH), another enzyme capable of cytoophidia formation [29].…”