(A) The injection scheme of thymidine analogs and tamoxifen. CldU and IdU were injected during postnatal weeks 2 and 3, respectively. The mice were fixed and double-stained with anti-CldU and anti-IdU antibodies. (B) The number of proliferated cells before and after KIF2A loss. The results are the means ± SD. (n = 15, three independent experiments. Student’ t-test, CldU p=0.61, IdU p=0.52). (C–F) Representative images of the immunostained dentate gyrus. E and F are magnified images of C and D. The broken white line indicates the bottom line of the GCL. Note that, in both WT (C and E) and cKO (D and F) mice, CldU-positive cells migrated slightly more than IdU-positive cells, and some aberrant cells migrated backward (blue arrowheads in the hilus) or ectopically (white arrowheads in the OML) from the bottom lines. (G–H) Representative graphs of the cell migration ratio. Zero represents the starting line for migrating cells at the bottom of the GCL. The distribution of CldU-positive cells and IdU-positive cells are shown in blue bars and red bars, respectively. (I) Statistical analysis of the cell migration ratio. The results are the means ± SEM. The average migration distance of CldU-positive cells (CldU(+)) and IdU-positive cells (IdU(+)) is not significantly different between WT (G) and cKO (H) cells. CldU (WT; n = 210, cKO; n = 235), and IdU (WT; n = 394, cKO; n = 364), three independent experiments. Welch’ t-test, (CldU;p=0.82, IdU;p=0.89). Abbreviations: IML, inner molecular layer; OML, outer molecular layer; GCL, granule cell layer; SGZ, sub granular zone. Bars: 20 μm in D and F.