日本高效培育出单亲实验鼠

生物谷

    生物谷报道：日本科学家２０日在《自然·生物技术》杂志网络版上发表论文说，他们借助孤雌生殖技术，只用卵子培育有生殖能力的实验鼠，成功率达到３０％。

    日本东京农业大学教授河野友宏的研究小组报告说，哺乳动物的基因中有一类叫作印记基因，通过ＤＮＡ甲基化等过程，这类基因只表达父母中一方的遗传信息，而关闭另一方的遗传信息。在这次培育实验鼠的过程中，他们使两个原本只通过精子遗传才发挥作用的印记基因，在只通过卵子遗传时也发挥作用，换句话说，就是使卵子具备雄性特征。

    将上述卵子的细胞核提取并注入别的卵子，两者融合后形成类似受精卵的细胞，再将这样的融合细胞移植入代孕母鼠的子宫。研究人员共移植了约９０个融合细胞，最终有４２只小雌鼠诞生，其中２７只顺利发育成拥有正常生殖能力的成年鼠。这２７只实验鼠除了体形较小以外，与正常实验鼠没有区别，其中已有５只繁殖了后代。

    河野友宏的研究小组曾于２００４年培育出只有母亲的实验鼠，但当时的成功率只有０．５％。这次研究人员改良了基因操作技术，使只有母亲的实验鼠的诞生几率超过４０％，发育为有生殖能力的成年鼠的几率达到３０％。（新华网）

原始出处:

Nature Biotechnology
Published online: 19 August 2007 | doi:10.1038/nbt1331

High-frequency generation of viable mice from engineered bi-maternal embryos

Manabu Kawahara1,2, Qiong Wu1,2,4, Nozomi Takahashi1, Shinnosuke Morita1, Kaori Yamada1, Mitsuteru Ito3, Anne C Ferguson-Smith3 & Tomohiro Kono1,2

Mammalian development to adulthood typically requires both maternal and paternal genomes, because genomic imprinting places stringent limitations on mammalian development, strictly precluding parthenogenesis1, 2. Here we report the generation of bi-maternal embryos that develop at a high success rate equivalent to the rate obtained with in vitro fertilization of normal embryos. These bi-maternal mice developed into viable and fertile female adults. The bi-maternal embryos, distinct from parthenogenetic or gynogenetic conceptuses, were produced by the construction of oocytes from fully grown oocytes and nongrowing oocytes that contain double deletions in the H19 differentially methylated region (DMR) and the Dlk1-Dio3 intergenic germline–derived DMR. The results provide conclusive evidence that imprinted genes regulated by these two paternally methylated imprinting-control regions are the only paternal barrier that prevents the normal development of bi-maternal mouse fetuses to term.

Department of BioScience Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan.
Bio-oriented Technology Research Advancement Institution (BRAIN), Minato-ku, Tokyo 105-0001, Japan.
Department of Physiology, Development & Neuroscience, University of Cambridge, Downing St., Cambridge CB2 3DY, UK.
Present address: Department of Life Science and Engineering Harbin Institute of Technology, No.92, West Da-Zhi Street, Harbin, Heilongjiang.

Correspondence to: Tomohiro Kono1,2 e-mail: tomohiro@nodai.ac.jp

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