In today’s Science online, researchers from the University Medical Center (UMC) Utrecht answer a question that has long been asked. During cell division how do cells distribute their doubled chromosomes in the correct way? The protein Aurora B appears to play a crucial role in this process. The incorrect distribution of chromosomes may lead to cancer, and also to Down’s syndrome.
During cell division, cells double all their chromosomes - the carriers of DNA. The two new cells both have to receive the same number of chromosomes. In the dividing cell, microtubules attach themselves to the original chromosome and its copy thus pulling them each to opposite sides. Only if these microtubules are attached to the chromosomes in the correct manner, is safe division guaranteed and can cell division continue.
In Science, Dr Susanne Lens and her colleagues from UMC Utrecht show that the protein Aurora B is able to detect whether or not the microtubules are properly attached. The protein detects the 'tension’ that arises when the microtubules pull each doubled chromosome to opposite sides. If there is no tension, Aurora B breaks the connection between the chromosomes and the microtubules and stops cell division.
If chromosomes are distributed incorrectly, for example, when Aurora B does not work properly, this may lead to the development of cancer. Therefore, the results of this research may possibly be a starting point for new anti-cancer therapies. In this way, fundamental knowledge of cell division supports cancer research.
Whilst the concept of ‘tension’ has been known for almost forty years, until recently no one had been successful in unravelling the molecular mechanism involved. Researchers at the Department of Medical Oncology at UMC Utrecht, are now working on this with their American colleagues at the University of Pennsylvania. The article has been published online in Science Express; a print version will follow.