Fig. 3: Galntl5 KO sperm lacking variants 1 and 2 show defects in ZP binding and migration into the oviduct.

a Fertilization rates with cumulus-intact eggs. Sperm from Galntl5 KO mice could fertilize eggs at a comparable level as sperm from Galntl5 Het mice [96.9 ± 2.7% (em2/wt), 100.0% (em2/em2)] (Mann–Whitney test, p = 0.40). ns: not significant. b Observation of sperm binding to the ZP. c Number of sperm bound to the ZP. Sperm from Galntl5 KO mice hardly bind to the ZP [sperm number/egg: 14.3 ± 4.3 (em2/wt), 1.3 ± 1.0 (em2/em2)] (Mann–Whitney test, p = 0.02). *p < 0.05. d Observation of sperm behavior in the female reproductive tract. Though the fluorescence-labeled sperm from Galntl5 KO mice abundantly exist in the uterus, these KO sperm hardly pass through the UTJ. The area dotted by the yellow color was magnified (lower panels). The data reproducibility was checked by five biological replicates. e Observation of sperm binding at the UTJ. The fluorescence-labeled WT sperm bind to the UTJ, but Galntl5 KO sperm hardly bind to the UTJ. Scale bars were 200 µm. Yellow-dotted lines show the border between the uterus and the oviduct. The data reproducibility was checked by two biological replicates (WT) and three biological replicates (KO).