Ross Pablo J, Cibelli Jose B
Department of Animal Science, Michigan State University, East Lansing, MI, USA.
Methods Mol Biol. 2010;636:155-77. doi: 10.1007/978-1-60761-691-7_10.
Somatic cell nuclear transfer (SCNT) is a technique by which the nucleus of a differentiated cell is introduced into an oocyte from which its genetic material has been removed by a process called enucleation. In mammals, the reconstructed embryo is artificially induced to initiate embryonic development (activation). The oocyte turns the somatic cell nucleus into an embryonic nucleus. This process is called nuclear reprogramming and involves an important change of cell fate, by which the somatic cell nucleus becomes capable of generating all the cell types required for the formation of a new individual, including extraembryonic tissues. Therefore, after transfer of a cloned embryo to a surrogate mother, an offspring genetically identical to the animal from which the somatic cells where isolated, is born. Cloning by nuclear transfer has potential applications in agriculture and biomedicine, but is limited by low efficiency. Cattle were the second mammalian species to be cloned after Dolly the sheep, and it is probably the most widely used species for SCNT experiments. This is, in part due to the high availability of bovine oocytes and the relatively higher efficiency levels usually obtained in cattle. Given the wide utilization of this species for cloning, several alternatives to this basic protocol can be found in the literature. Here we describe a basic protocol for bovine SCNT currently being used in our laboratory, which is amenable for the use of the nuclear transplantation technique for research or commercial purposes.
体细胞核移植（SCNT）是一种技术，通过该技术，将分化细胞的细胞核引入一个卵母细胞中，卵母细胞的遗传物质已通过一种称为去核的过程被去除。在哺乳动物中，人工诱导重构胚胎启动胚胎发育（激活）。卵母细胞将体细胞核转变为胚胎细胞核。这个过程称为核重编程，涉及细胞命运的重要改变，通过这种改变，体细胞核能够产生形成一个新个体所需的所有细胞类型，包括胚外组织。因此，将克隆胚胎移植到代孕母体后，会诞生一个与分离出体细胞的动物基因相同的后代。通过核移植进行克隆在农业和生物医学中有潜在应用，但受到效率低下的限制。牛是继多利羊之后第二个被克隆的哺乳动物物种，并且它可能是体细胞核移植实验中使用最广泛的物种。这部分是由于牛卵母细胞的高可用性以及通常在牛中获得的相对较高的效率水平。鉴于该物种在克隆中的广泛应用，文献中可以找到几种对这个基本方案的替代方法。在这里，我们描述了一种目前在我们实验室中使用的牛体细胞核移植基本方案，该方案适用于将核移植技术用于研究或商业目的。
