Western blot analysis of Uox protein expression in homozygous B-Uox KO mice. Liver, kidney, lung, spleen, heart and brain were collected from C57BL/6 wild-type mice (+/+) and homozygous B-Uox KO mice (-/-)，and then analyzed by western blot with species-specific anti-Uox antibody. 40 μg total proteins were loaded for western blotting analysis. Uox was not detected in liver of homozygous B-Uox KO mice (-/-).

Efficacy validation. Mice were divided into 4 groups(male, 5 week-old, n=3-5/group), C57BL/6, B-Uox KO mice (+/-), B-Uox KO mice (-/-), Uox-KO mice with 100μg/ml allopurinol in drinking water (B-Uox KO mice (-/-), allopurinol). Compared with C57BL/6 mice, serum uric acid level of B-Uox KO mice (-/-) was significantly increased, and the intervention of allopurinol could significantly reduce the serum uric acid level of B-Uox KO mice (-/-). Values are expressed as mean ± SEM.