BAIAP2 and Anxiety: Intriguingly, in another anxiety-related behavioral test (light-dark test), which was not previously performed for IRSp53-cKO or IRSp53-global-KO mice29,31, IRSp53-cKO mice injected with PHP.eB-EGFP (control) spent less time in the light chamber and visited the light chamber less frequently (Fig. 3c), which was suggestive of baseline anxiety-like behavior.