Fukami K, Nakao K, Inoue T, Kataoka Y, Kurokawa M, Fissore R A, Nakamura K, Katsuki M, Mikoshiba K, Yoshida N, Takenawa T
Department of Biochemistry, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8039, Japan.
Science. 2001 May 4;292(5518):920-3. doi: 10.1126/science.1059042.
Several phospholipase C (PLC) isoforms have been found in male and female mammalian gametes, and splicing isoforms of PLCdelta4 are predominantly expressed in testis. Here we report that male mice in which the PLCdelta4 gene had been disrupted either produced few small litters or were sterile. In vitro fertilization studies showed that insemination with PLCdelta4-/- sperm resulted in significantly fewer eggs becoming activated and that the calcium transients associated with fertilization were absent or delayed. PLCdelta4-/- sperm were unable to initiate the acrosome reaction, an exocytotic event required for fertilization and induced by interaction with the egg coat, the zona pellucida. These data demonstrate that PLCdelta4 functions in the acrosome reaction that is induced by the zona pellucida during mammalian fertilization.
在雄性和雌性哺乳动物配子中已发现几种磷脂酶C（PLC）亚型，其中PLCδ4的剪接亚型主要在睾丸中表达。在此我们报告，PLCδ4基因被破坏的雄性小鼠要么产仔很少且窝仔小，要么不育。体外受精研究表明，用PLCδ4基因敲除的精子进行授精时，被激活的卵子显著减少，且与受精相关的钙瞬变缺失或延迟。PLCδ4基因敲除的精子无法引发顶体反应，而顶体反应是受精所需的一种胞吐事件，由与卵膜（透明带）相互作用诱导产生。这些数据表明，PLCδ4在哺乳动物受精过程中由透明带诱导的顶体反应中发挥作用。
