New Study on DNA Replication Reveals how DNA Times its Replication

Despite over a century of research on molecular genetics, many mysteries still remain. Researchers today, though, have discovered details surrounding how DNA times its replication.

"It's been quite a mystery," said David Gilbert, a molecular biologist from Florida State University. "Replication seemed resilient to everything we tried to do to perturb it. We've described it in detail, shown it changes in different cell types and that it is disrupted in disease.
"But until now, we couldn't find that final piece, the control elements or the DNA sequences that control it."

In order to figure out how the timing of DNA replication works, Gilbert, along with his team, used CRISPR to cut mouse chromosomes in order to find the factors affecting timing. CRISPR was used to target, switch, or cut out different structures within mouse embryonic stem cells. At first, the team focused on the binding sites for a protein called CCCTC-C binding factor (CTCF), but it was soon realized that this had little effect on the timing. By using a high resolution 3D analysis of the contact sites that the DNA was making with itself, the team identified key spots outside of CTCF associated boundaries. When breaking these spots, the timing of replication was thrown off.

Further research on the timing of replication may lead to breakthroughs in health and pathology research. Specifically, the processes that cause certain diseases.

“We've come a long way since the physicist Erwin Schrödinger delivered his prediction of an 'aperiodic crystal' that could explain the replication of a cell using little more than the physics of basic chemistry, ” said Gilbert.

Read more about this fascinating story at: https://www.sciencealert.com/new-study-solves-the-decades-old-mystery-on-how-dna-manages-its-own-replication