Chromosome glue repairs damaged DNA

July 13, 2007

When a strand of DNA breaks in the body's cells, it normally does not take long until it has been repaired. Now researchers at the Swedish medical university Karolinska Institutet have discovered a new mechanism that helps to explain how the cell performs these repairs. The results are presented in Science.

The new results are concerned with a phenomenon called cohesion, whereby two copies of a chromosome in the cell nucleus are held tightly together by a protein complex called cohesin.

Cohesion fulfils an important function during cell division as the newly copied chromosomes, the sister chromatids, have to stay together until the right moment of separation. If the chromatids come apart too early, there is a risk of the daughter cells getting the wrong number of chromosomes, something that is often observed in tumour cells.

Dr Camilla Sjögren and her research team have now shown that the cell also employs cohesion to repair damaged sister chromatids. Their results show that DNA damage can reactivate cohesin, which runs counter to the commonly held view that cohesion only arises during the DNA copying that takes place before cell division.

Scientists have long been fascinated by the way in which the duplicated chromosomes are separated before cell division so that exactly half the copied genetic material ends up in each daughter cell. Another large research question is how cells repair damaged DNA and consequently prevent cancer, for example.

"We have shown that chromosome segregation and DNA repair are partly dealt with by the same machinery. These findings provide new understanding of two fundamental cellular mechanisms and may also be of value to cancer research," says Dr Sjögren.

Source: Karolinska Institutet

Explore further: HPV16 DNA from fine-needle aspirations OK for diagnosis

Related Stories

HPV16 DNA from fine-needle aspirations OK for diagnosis

December 6, 2016

(HealthDay)—HPV16 DNA detected in fine-needle aspirations from neck masses is a reliable indicator for diagnosis of an HPV-positive oropharyngeal squamous cell carcinoma (SCC), according to a study published Nov. 29 in ...

What happens in the cell nucleus after fertilization

December 6, 2016

A team of scientists at the Helmholtz Zentrum München shows changes in the immediate environment of DNA after the ovum and sperm fuse to form the zygote. The results suggest why all conceivable somatic cells can develop ...

How the tuberculosis vaccine may protect against other diseases

December 6, 2016

The tuberculosis vaccine is well known to help protect against other infectious diseases, as well as cancer, but the exact mechanisms have not been clear. A study published December 6 in Cell Reports now shows that the broad-spectrum ...

Recommended for you

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.