Department of Cell Science, Institute of Biomedical Sciences, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima City, Fukushima 960-1295, Japan.
Int J Mol Sci. 2019 Sep 27;20(19):4809. doi: 10.3390/ijms20194809.
Sperm-egg fusion is accomplished through the interaction of a specific set of membrane proteins in each gamete: sperm IZUMO1 and oocyte JUNO. Recently, we found that alternative splicing of the gene generates a novel IZUMO1 isoform (IZUMO1_v2). Here, we obtained four mouse lines, having graded different levels of IZUMO1 protein by combining an original IZUMO1 (IZUMO1_v1) knockout with IZUMO1-null (both IZUMO1_v1 and _v2 disrupted) genetic background, in order to determine how the quantity of IZUMO1 influences male fertility. Subsequently, we clarified that the signal intensity from two quantitative assays, western blot and immunostaining analyses with a monoclonal antibody against mouse IZUMO1, were strongly correlated with average litter size. These results suggest that evaluating IZUMO1 protein levels is useful for predicting fecundity, and is a suitable test for male fertility.
精子 IZUMO1 和卵子 JUNO。最近，我们发现基因的可变剪接产生了一种新的 IZUMO1 同工型（IZUMO1_v2）。在这里，我们获得了四条鼠系，通过将原始 IZUMO1（IZUMO1_v1）敲除与 IZUMO1 缺失（IZUMO1_v1 和 _v2 均被破坏）遗传背景相结合，产生了不同程度的 IZUMO1 蛋白，以确定 IZUMO1 的数量如何影响雄性生育能力。随后，我们阐明了两种定量检测方法的信号强度，即western blot 和针对小鼠 IZUMO1 的单克隆抗体的免疫染色分析，与平均产仔数呈强相关。这些结果表明，评估 IZUMO1 蛋白水平有助于预测生育能力，是一种适合男性生育力的检测方法。
