{"id":6722,"date":"2016-03-21T14:00:28","date_gmt":"2016-03-21T13:00:28","guid":{"rendered":"http:\/\/news.embl.de\/?p=6722"},"modified":"2024-03-25T10:28:30","modified_gmt":"2024-03-25T09:28:30","slug":"1603-centrioles","status":"publish","type":"post","link":"https:\/\/www.embl.org\/news\/science\/1603-centrioles\/","title":{"rendered":"Mothers and daughters"},"content":{"rendered":"\n

EMBL scientists have observed how an egg cell gets rid of its centrioles \u2013 structures that play a crucial role in cell division \u2013 to ensure the proper development of the embryo. The study, published today in Journal of Cell Biology<\/em>, is the first time the whole process has been seen in its entirety, in real time.<\/p>\n\n\n\n

The basics of sexual reproduction appear to be very simple: sperm plus egg cell equals embryo. But within cells, it gets trickier: simply combining the genetic content of two cells would lead to disaster; every generation would carry twice as much DNA as its parents. To prevent this, egg and sperm cells halve their genetic content before fusing. A similar issue arises with structures called centrioles.<\/p>\n\n\n\n

People have tagged a mother centriole in the sperm, and found it still intact in the late embryo!<\/p><\/blockquote>\n\n\n\n

Centrioles act as anchors for the spindle apparatus, which pulls genetic material apart during cell division. If a fertilised egg has centrioles from both the egg cell and the sperm, its genetic material will be pulled in too many directions and it will be shared unevenly between the resulting cells, which is likely to make the embryo unviable. So in animals, before an egg cell is fertilised by a sperm, its centrioles are eliminated, ensuring that the resulting embryo receives only the sperm\u2019s centrioles.<\/p>\n\n\n\n

When a cell is dividing, each anchor point is actually a pair of centrioles: a mature \u2018mother\u2019 centriole, and an immature \u2018daughter\u2019 centriole.<\/p>\n\n\n\n

\u201cMother centrioles are known to be very, very stable,\u201d says P\u00e9ter L\u00e9n\u00e1rt<\/a> from EMBL, who led the work. \u201cIn the worm C.elegans<\/em>, people have tagged a mother centriole in the sperm, and found it still intact in the late embryo!\u201d<\/p>\n\n\n\n

To investigate how the egg cell manages to rid itself of such a resilient structure, Joana Pinto, a PhD student in the L\u00e9n\u00e1rt lab, developed fluorescent tags for mother and daughter centrioles in a starfish egg cell and recorded the entire process of eliminating them.<\/p>\n\n\n