Beath Elizabeth A, Bailey Cynthia, Magadum Meghana Mahantesh, Qiu Shuyan, McNally Karen L, McNally Francis J
Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95618, USA.
bioRxiv. 2024 Jun 26:2024.03.12.584242. doi: 10.1101/2024.03.12.584242.
Fertilization occurs before completion of oocyte meiosis in the majority of animal species and sperm contents move long distances within zygotes of mouse and . If incorporated into the meiotic spindle, paternal chromosomes could be expelled into a polar body resulting in lethal monosomy. Through live imaging of fertilization in , we found that the microtubule disassembling enzymes, katanin and kinesin-13 limit long range movement of sperm contents and that maternal ataxin-2 maintains paternal DNA and paternal mitochondria as a cohesive unit that moves together. Depletion of katanin or double depletion of kinesin-13 and ataxin-2 resulted in capture of the sperm contents by the meiotic spindle. Thus limiting movement of sperm contents and maintaining cohesion of sperm contents within the zygote both contribute to preventing premature interaction between maternal and paternal genomes.
在大多数动物物种中，受精发生在卵母细胞减数分裂完成之前，并且精子内容物在小鼠合子内移动很长距离。如果父本染色体被并入减数分裂纺锤体，可能会被排出到极体中，导致致死性单体性。通过对受精过程的实时成像，我们发现微管解聚酶katanin和驱动蛋白-13限制了精子内容物的长距离移动，并且母本ataxin-2将父本DNA和父本线粒体维持为一个共同移动的凝聚单元。katanin的缺失或驱动蛋白-13和ataxin-2的双重缺失导致减数分裂纺锤体捕获精子内容物。因此，限制精子内容物的移动并维持合子内精子内容物的凝聚性都有助于防止母本和父本基因组之间的过早相互作用。
