From local DNA folding to the shape of a chromosome

How do changes in small DNA packages influence whole chromosomes?

Scientific context

How it works

Inside cells, long DNA strands wrap around proteins to form many small units called nucleosomes. By watching how individual nucleosomes move, we can learn how the entire chromosome holds its structure.

Treating a chromosome as one thick thread does not reveal which regions inside it are held tightly and which can move more freely. Tracking individual nucleosomes provides a way to measure these local constraints.

In a 2024 study, we followed individual nucleosomes inside mitotic chromosomes. The results showed that condensin and interactions between neighboring nucleosomes restrict DNA movement in different ways.

Evidence & open questions

What we want to learn next

Published research

We aim to connect these molecular measurements to the overall shape and behavior of chromosomes, linking events at very different scales.

Literature

Related publications & press releases

Nature Communications (2024)Single-nucleosome imaging unveils that condensins and nucleosome–nucleosome interactions differentially constrain chromatin to organize mitotic chromosomes

Measurements of individual nucleosomes clarify how condensin activity and contacts within chromatin shape mitotic chromosomes.

Original publication ↗Press release ↗