Fig. 4.

Agglomeration in evolution. a Model of allosteric regulation for human and E. coli CTPS. Although filament formation is present in both organisms, it has opposite effects on the enzyme activity (adapted with permission of Lynch et al. (2017)). b In S. cerevisiae, the enzyme glutamine synthase (Gln1) and the transcription initiation factor eIF2B (Gcn3) form filaments upon glucose deprivation (adapted from Petrovska et al. 2014, and Nüske et al. 2020). c Hydrogen peroxide–induced polymerization of the enzyme 2-cys peroxiredoxin serves as a functional switch from peroxidase to chaperone activity (adapted with permission from Saccoccia et al. 2012). d TEM image displaying eIF2B filaments in a starved yeast cell (image reproduced from Marini et al. 2020)