Western blot analysis of FMRP protein expression in homozygous B-Fmr1 KO mice. Various tissue lysates were collected from wild-type C57BL/6 mice (+/+) and homozygous B-Fmr1 KO mice (-/Y), and then analyzed by western blot with anti-FMRP antibody. 40 μg total proteins were loaded for western blotting analysis. FMRP was not detectable in homozygous B-Fmr1 KO mice.

Male B-Fmr1 KO mice show significant hyperactivity in the open field test. C57BL/6 mice and B-Fmr1 KO mice at 2 to 3 months of age were placed in an open field arena, and allowed to freely explore for 2 hours. The total movement distance (A), average speed (B), number of feces pellet (C), time spent in the periphery and center (D,E), and number of crossing in the periphery and center (F,G) were scored. Data presented as mean ± SEM were analyzed by T-test. n=10, *P < 0.05.