Growing an Embryo from a Single Cell: A Hurdle in Animal Life.
Growing an Embryo from a Single Cell: A Hurdle in Animal Life.
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DOI：
10.1101/cshperspect.a019042
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发表时间：
2015-08-07
影响因子：
7.2
通讯作者：
O'Farrell PH
中科院分区：
文献类型：
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作者：
O'Farrell PH
动物必须能够进食才能生长的要求限制了细胞如何生长成动物，并且它迫使生长（质量增加）和增殖（细胞数量增加）之间的交替。在将普通比例的干细胞转化为巨大细胞（卵母细胞）的生长阶段，需要进行戏剧性的调整，以帮助细胞核引导细胞质体积扩大105倍。没有生长的增殖将巨大的卵子转化为胚胎，同时仍然容纳被大量细胞质淹没的无能细胞核。这种生长程序的特点是动物的存款他们的鸡蛋外，但它是改变了哺乳动物和体内寄生虫。在这些生物体中，在营养环境中的发育释放了生长限制，但是在原肠胚形成之前的细胞生长需要一个新的程序来维持这种生长期间的多能性。
A requirement that an animal be able to feed to grow constrains how a cell can grow into an animal, and it forces an alternation between growth (increase in mass) and proliferation (increase in cell number). A growth-only phase that transforms a stem cell of ordinary proportions into a huge cell, the oocyte, requires dramatic adaptations to help a nucleus direct a 105-fold expansion of cytoplasmic volume. Proliferation without growth transforms the huge egg into an embryo while still accommodating an impotent nucleus overwhelmed by the voluminous cytoplasm. This growth program characterizes animals that deposit their eggs externally, but it is changed in mammals and in endoparasites. In these organisms, development in a nutritive environment releases the growth constraint, but growth of cells before gastrulation requires a new program to sustain pluripotency during this growth.