Life Support

Getting from fertilised egg to viable embryo is a labour-intensive process with endless logistics and huge energy demands. Oocytes, or egg cells, completely rely on a part of the cell called mitochondria for ATP – their source of energy. To keep up with energy demands, the number of mitochondria in an oocyte needs to boom from 1,000 to 300,000 through a process called mitochondrial fission – splitting into two. This splitting is driven by a protein called DRP1, but how DRP1 and fission affect embryo development was unclear. Deleting DRP1 from mouse oocytes meant that crucial genes that kickstart development couldn’t be switched on. The switches in the form of methylation marks (shown in green and magenta) are lost from the DNA without DRP1, and so the embryos cannot survive. Together, this shows how important the mitochondria are to the early stages of embryo development and survival.

Written by Sophie Arthur

Sophie Arthur

former Science Communications Officer MRC LMS

Formerly a stem cell biologist, Sophie has since moved into science communication working at the MRC LMS. She also writes an award winning science and education blog Soph talks science.

Website

• Image from work by Deepak Adhikari and colleagues
• Development and Stem Cell Program and Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia.
• Image originally published with a Creative Commons Attribution 4.0 International (CC BY-NC 4.0)
• Published in Science Advances, June 2022