Eggsplosion!
One of life’s most delicate processes starts with an explosion. This mouse’s ovarian follicle prepares to launch an egg at high speed – the black circle here (~100 times smaller than a cannonball). Like a lot of dramatic biological events, ovulation is usually hidden from view, so scientists find innovative ways to examine its steps. Bathing this mouse follicle in nurturing chemicals under a microscope, scientists use fluorescent dyes to highlight its membrane (green) and the liquid inside (red). They find that first, the follicle expands, filling up with chemicals rushing in from its surroundings. Fit to burst, muscle cells on the outside squeeze the follicle, which ruptures at a thin part of its wall, propelling the egg on its way. Perhaps starting from a similar blast, the journey from human ovulation to fertilisation to pregnancy is still full of mystery, relying on experiments like these for clues.
Written by John Ankers
Video from work by Christopher Thomas and Tabea Lilian Marx, and colleagues
Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
Video originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)
Published in Nature Cell Biology, October 2024
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