Centrosome inheritance in starfish zygotes: selective loss of the maternal centrosome after fertilization.
Centrosome inheritance in starfish zygotes: selective loss of the maternal centrosome after fertilization.
复制标题
海星受精卵的中心体遗传：受精后母体中心体的选择性丢失。
DOI：
10.1016/s0012-1606(89)80027-2
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发表时间：
1989
影响因子：
2.7
通讯作者：
Rieder,CL
中科院分区：
文献类型：
--
作者：
Sluder,G;Miller,FJ;Lewis,K;Davison,ED;Rieder,CL
成熟的卵子继承了第二减数分裂纺锤体的中心体，精子在受精时引入了第二中心体。由于这些中心体中只有一种能够存活下来用于发育，因此必须存在特定的机制来控制中心体遗传。为了研究中心体遗传是如何控制的，我们使用海星卵作为模型系统，因为它们在受精后经历减数分裂。因此，母本和父本中心体的命运可以通过光学显微镜观察并在体内进行实验操作。我们最初表明，只有父本中心体用于海星受精卵的发育；从减数分裂 II 中保留的母体中心体在第一次有丝分裂之前功能性丧失。然后，我们测试了多种可能的方式，使受精卵能够对最初驻留在同一细胞质中的中心体的稳定性施加这种差异控制。这些实验的结果可概括如下：(1)尽管母体中心体的微管组织中心活性在减数分裂后并未降低，但该中心体在连续有丝分裂中加倍的能力丧失了。 (2) 精子中心体不会被细胞质条件“掩盖”，细胞质条件可能会在减数分裂序列期间或之后破坏所有中心体的稳定性。 (3)母体中心体的功能丧失并不是由于其皮质位置所致。 (4) 这种倍增能力的丧失是由卵子决定的，而不是由受精精子的假定抑制因素决定的。 (5)母体中心体的不稳定并不是由于其中心粒完全丧失。总之，这些结果表明所有母本中心体都是等效的，并且它们与父本中心体有本质上的不同。这种内在的差异，与减数分裂后细胞质条件的变化相一致，决定了从减数分裂 II 纺锤体继承的母体中心体的选择性损失。
The mature egg inherits a centrosome from the second meiotic spindle, and the sperm introduces a second centrosome at fertilization. Since only one of these centrosomes survives to be used in development, specific mechanisms must exist to control centrosome inheritance. To investigate how centrosome inheritance is controlled we used starfish eggs as a model system, because they undergo meiosis after fertilization. As a result, the fate of the maternal and paternal centrosomes can be followed by light microscopy and experimentally manipulatedin vivo. We show initially that only the paternal centrosome is used in starfish zygote development; the maternal centrosome retained from meiosis II is functionally lost before first mitosis. We then tested a number of possible ways in which the zygote could exert this differential control over the stability of centrosomes initially residing in the same cytoplasm. The results of these experiments can be summarized as follows: (1) Although the microtubule organizing center activity of the maternal centrosome is not degraded after meiosis, the ability of this centrosome to double at successive mitoses is lost. (2) The sperm centrosome is not “masked” from cytoplasmic conditions which could destabilize all centrosomes during or after the meiotic sequence. (3) The functional loss of the maternal centrosome is not due to its cortical location. (4) The loss of this doubling capacity is determined by the egg, not by putative inhibitory factors from the fertilizing sperm. (5) The destabilization of the maternal centrosome is not due to the complete loss of its centrioles. Together, these results demonstrate that all maternal centrosomes are equivalent and that they are intrinsically different from the paternal centrosome. This intrinsic difference, in concert with a change in cytoplasmic conditions after meiosis, determines the selective loss of the maternal centrosome inherited from the meiosis II spindle.