Western Blot Analysis of Metabolic Enzymes

Mouse tissues were homogenized and lysed by using RIPA buffer (Santa Cruz Biotechnology). Protein contents were measured by using the Bradford assay (Pierce Biotechnology). Detailed steps for western blot analysis were as previously described^{59 (link)}. The primary antibodies included goat anti-KYNU, rabbit anti-KMO, mouse anti-KAT1, mouse anti-Cyclin B1, mouse anti-GAPDH (all above antibodies from Santa Cruz Biotechnology); mouse anti-YAP1, mouse anti-phospho-YAP (ser 127), rabbit anti-Erk1/2 (Thr202/Tyr204), rabbit anti-Erk1/2, rabbit anti-c-Myc, rabbit anti-phospho-Src (Tyr527) and rabbit anti-Src (all seven antibodies from Cell Signaling). The relative protein levels were calculated by normalizing to GAPDH protein as a loading reference by using ImageJ.