The knowledge may also be legally relevant. For some countries, including Germany, as beginning of Schützenswürdigen human life, set merger of parental nuclei after fertilization. If process in humans is similar to that of examined mice embryos, it would be a few hours later than intended for emergence of new life.
Explanation for errors in first cell splitsThe newly discovered double spindle could also explain part of high error rate in first cell divides of mammals. Errors in separation of chromosomes may form cells with several cell nuclei, a common reason why an embryo does not evolve. "The goal of this project was to find out why re are so many mistakes in first splits," says Jan Ellenberg, head of project at EMBL. "We already knew that with simpler animals such as insects, two spindles would be formed, but would never have suspected that this is case for mammals like mice as well." In future, it is important to find out wher process is same in humans, says Ellenberg. This could also make progress in research into human infertility.
The results could also solve an old enigma of embryology: parental chromosomes are arranged in round cell nuclei of zweizel embryos to two crescents. So far, re has been no conclusive explanation for this phenomenon. "At first we tracked movements of parental chromosomes, but we could not find a cause for this distribution," says Judith Reichmann, a scientist at EMBL and first author of article. "Only when we focused our attention on microtubules – dynamic structures that make up spindles – we were able to see double spindles for first time."
Of course, results are not entirely new, explains Michael Boiani, head of Working group "mouse Embryology" at Max Planck Institute for Molecular Biomedicine Münster to Science Media Center Deutschland: "It was already shown in year 2005 on Mice (Nature: Plusa et al. ) that chromosomes of maternal and paternal core are not mixed with each or in resulting spindle. " The study now published, however, is a mechanistic explanation with discovery of two spindles.
The discovery was made possible only by a technical innovation developed by EMBL researchers *: Light leaf microscopy. Embryos are very sensitive to light in early stages of development and are damaged by conventional light microscopy methods. Due to new method y are only illuminated very briefly and spatially, so that even hirto hidden processes can be observed.
* Note: In a previous version it was said that EMBL researchers had developed Lichblattmikroskopie. That is not correct. They have only furr developed technology that has been discovered a long time ago. We ask you to apologize for this inaccuracy.
Date Of Update: 14 July 2018, 12:02