Medical Research Council - London Institute of Medical Sciences

Now in our 12th year of bringing you beautiful imagery from biomedical science every day

Exit for Two

Role of the subnuclear organelle –  the nucleolus – in embryo development

19 July 2022

Exit for Two

We all begin as one cell which divides into two – but for an embryo to advance further in development, a so-called jumping gene MERVL needs to be rapidly switched off. MERVL is known to be controlled by a factor called Dux, but how Dux is regulated and affects exit from the two-cell stage was unclear. Now, researchers have discovered that the cell’s nucleolus plays a role in regulating Dux. The nucleolus (pictured; DNA in cyan, nucleolus compartments in various colours) is part of our cell’s headquarters – the nucleus – and responsible for making our protein-making factories called ribosomes, and not commonly associated with gene regulation. By disrupting the nucleolus, Dux quickly re-activated, leading to increased levels of MERVL keeping the embryo stuck at the two-cell stage. Not only does embryonic exit from the two-cell stage require genes, like MERVL, to be switched off, the embryo also requires a functioning nucleolus to advance.

Read more on this research from the MRC London Institute of Medical Sciences here

Written by Sophie Arthur

Search The Archive

Submit An Image

What is BPoD?

BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

Read More

BPoD is also available in Catalan at with translations by the University of Valencia.