Figure 8. The regulation of M2PYK by metabolites.

M2PYK is at the intersection of metabolic pathways (shown with black arrows). Blue solid arrows show the transformation of M2PYK among active tetramer (green), inactive tetramer (orange), and monomer (orange). Green dotted arrows show that FBP and serine stabilise M2PYK in the active tetrameric form, and thereby activate its enzymatic activity. In contrast, phenylalanine, tryptophan, valine, and alanine inhibit M2PYK enzymatic activity by stabilising it in an inactive tetrameric form (shown with orange dotted arrows). Autophagic alanine secretion from neighbouring cells [51] are shown in purple.