Eisen A, Reynolds G T
J Cell Biol. 1984 Nov;99(5):1878-82. doi: 10.1083/jcb.99.5.1878.
Maturation and fertilization of the starfish oocyte are putative calcium-dependent events. We have investigated the spatial distribution and temporal dynamics of this calcium dependence in single oocytes of Asterias forbesi. We used the calcium photoprotein, aequorin, in conjunction with a microscope-photomultiplier and microscope-image intensifier. Surprisingly, in contrast to earlier work with Marasthenias glacialis, there is no detectable increase in intracellular-free calcium in the oocyte of A. forbesi in response to the maturation hormone 1-methyl adenine. During fertilization of the same, matured, A. forbesi oocyte there is a large increase in intracellular-free calcium. The calcium concentration increases to approximately 1 microM at the point of insemination and the region of elevated free calcium expands across the oocyte in approximately 20 s (17-19 degrees C). After the entire oocyte reaches an elevated concentration of free calcium, the concentration decreases uniformly throughout the oocyte over the next several minutes.
海星卵母细胞的成熟和受精被认为是依赖钙的过程。我们研究了福布斯海盘车单个卵母细胞中这种钙依赖性的空间分布和时间动态。我们将钙光蛋白水母发光蛋白与显微镜光电倍增管和显微镜图像增强器结合使用。令人惊讶的是，与早期对冰川海螂的研究不同，福布斯海盘车卵母细胞在成熟激素1-甲基腺嘌呤的作用下，细胞内游离钙没有可检测到的增加。在同一成熟的福布斯海盘车卵母细胞受精过程中，细胞内游离钙大幅增加。受精时钙浓度增加到约1微摩尔，游离钙升高区域在约20秒内（17 - 19摄氏度）扩展穿过整个卵母细胞。在整个卵母细胞达到游离钙升高浓度后，浓度在接下来的几分钟内均匀下降。
