• Uox mainly expressed in the liver and involved in allantoin metabolic process, purine-containing compound catabolic process and urate catabolic process. 
• The exons 3~4 of mouse Uox gene were knocked out in B-Uox KO mice plus (C57BL/6J). 
• It was proved that there was no expression of Uox protein in the liver of B-Uox KO mice and the uric acid in the blood was significantly increased.
• Allopurinol could significantly reduce the serum uric acid level of B-Uox KO mice plus.
• B-Uox KO mice plus can be used for pharmacological evaluation of hyperuricemia, gout, etc.

Western blot analysis of Uox protein expression in homozygous B-Uox KO mice plus. Liver, kidney, lung, spleen, heart, and brain were collected from C57BL/6 wild-type mice (+/+) and homozygous B-Uox KO mice plus (-/-)， and then analyzed by western blot with species-specific anti-Uox antibody (Santa cruz，sc-166214). 40 μg total proteins were loaded for western blotting analysis. Uox was not detected in liver of homozygous B-Uox KO mice plus (-/-).

Efficacy validation in B-Uox KO mice plus. Mice were divided into 3 groups (male, 6 weeks), C57BL/6 (n=4), B-Uox KO mice plus (n=1), B-Uox KO mice plus with 100μg/ml allopurinol in drinking water from 6 weeks to 8 weeks (n=4). Compared with C57BL/6 mice (+/+), serum uric acid level of B-Uox KO mice plus (-/-) was significantly increased, and the intervention of allopurinol could significantly reduce the serum uric acid level of B-Uox KO mice plus (-/-). Values are expressed as mean ± SEM.

Efficacy validation in B-Uox KO mice plus. Mice were divided into 2 groups (male, 10-11 weeks-old, n=2), of B-Uox KO mice plus and of B-Uox KO mice plus with 100μg/ml allopurinol in drinking water. Allopurinol could significantly reduce the serum uric acid level of B-Uox KO mice plus (-/-). Values are expressed as mean ± SEM.