Doing the Splits

Our bodies are constantly making cells – new ones for growth, and replacement ones for damaged or dead cells. But cells don’t just appear. They are manufactured when an existing cell makes a copy of its DNA-containing chromosomes (shown in pink), and then splits to produce two, identical new cells. Cells can split in any orientation – up/down, left/right, diagonally – but the split needs to generate two equal halves, a process not left to chance. Scientists have been researching a protein LGN (shown in green) that plays a role in balancing the division. The normal cell (left) sees chromosomes line up down the middle between two crescents of LGN. When they used a drug to shift the chromosomes off-centre (right), the pattern of LGN signalling changed. The chromosomes themselves seem to influence the signal. Unpicking cause from effect in molecular systems is a complex business.

Written by Helen Pilcher

Helen Pilcher

Writer

Helen is a freelance science writer who lives in rural Warwickshire. She studied Neuroscience and has a PhD in stem cell biology, but now writes news, features and opinion pieces about science for magazines and the internet.

• Tomomi Kiyomitsu
• Cheeseman Lab, Whitehead Institute for Biomedical Research, USA
• Reprinted by permission from Macmillan Publishers Ltd: Nature Cell Biology, Copyright 2012
• Published in Nature Cell Biology