Navigation Links
Discovery of cell division 'master controller' may improve understanding and treatment of cancer
Date:9/11/2013

Hanover, NH In a study to be published in the journal Nature, two Dartmouth researchers have found that the protein cyclin A plays an important but previously unknown role in the cell division process, acting as a master controller to ensure the faithful segregation of chromosomes during cell division.

Cell division is the process in which cells reproduce by splitting into two identical copies. This process happens trillions of times in an average person's lifetime. To generate two identical copies, cells must separate their chromosomes precisely, an event that relies on the bi-oriented attachment of chromosomes to spindle microtubules through specialized structures called kinetochores. In the early phases of division, there are numerous errors in how kinetochores bind to spindle microtubules. Normal cells efficiently correct these errors so that chromosomes segregate faithfully. However, cancer cells generally do not correct these errors, resulting in daughter cells with abnormal numbers of chromosomes, which may help these cancer cells develop resistance to chemotherapy treatments.

In their study, Dartmouth researchers Lilian Kabeche, PhD, and Duane Compton, PhD, show that microtubule attachments at kinetochores are very unstable in early phases of division. The unstable attachments promote the correction of errors by causing a constant detachment, realignment and reattachment of microtubules from kinetochores in the cells as they try to find the correct attachment. Their study found that the protein cyclin A governs this process by keeping the process going until the errors are eliminated.

"An analogy for this process could be dating," said Compton, Senior Associate Dean for Research and professor of biochemistry at Dartmouth's Geisel School of Medicine. "The chromosomes are testing the microtubules for compatibilitythat is, looking for the right matchto make sure there are correct attachments and no errors. The old view of this process held that chromosomes and microtubules pair up individually to find the correct attachment, like conventional dating. However, our results show that the system is more like speed dating. All the chromosomes have to try many connections with microtubules in a short amount of time. Then they all make their final choices at the same time. Cyclin A acts like a timekeeper or referee to make sure no one makes bad connections prematurely."

In normal cells, persistent cyclin A expression prevents the stabilization of microtubules bound to kinetochores even in cells with aligned chromosomes. As levels of cyclin A decline, microtubule attachments become stable, allowing the chromosomes to be divided correctly as cell division proceeds. In contrast, in cyclin A-deficient cells, microtubule attachments are prematurely stabilized. Consequently, these cells may fail to correct errors, leading to higher rates of chromosome mis-segregation.

"Many cancer cells continuously mis-segregate their chromosomes," says Kabeche. "The major cause is improper kinetochoremicrotubule attachments. Therefore, understanding how kinetochoremicrotubule attachments are regulated throughout cell division is important, not only for furthering our understanding of cell division, but also for allowing us to correct these problems in cancer cells."


'/>"/>

Contact: Derik Hertel
derik.hertel@dartmouth.edu
603-650-1211
The Geisel School of Medicine at Dartmouth
Source:Eurekalert

Related biology news :

1. Discovery of a molecule that initiates maturation of mammalian eggs can lead to more IVF pregnancies
2. Annual Drug Discovery Conferences Being Held in Boston MA, Spring 2012
3. Discovery provides blueprint for new drugs that can inhibit hepatitis C virus
4. Unexpected discovery reveals a new mechanism for how the cerebellum extracts signal from noise
5. Discovery offers insight into treating viral stomach flu
6. Breast cancer risk gene discovery fast tracked by new technology
7. Tales from the crypt lead researchers to cancer discovery
8. New discovery may lead to effective prevention and treatment of graft-versus-host dsease
9. Stomata development in plants unraveled -- a valuable discovery for environmental research
10. Discovery reveals chromosomes organize into yarns
11. Bacteria discovery could lead to antibiotics alternatives
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/27/2016)... , June 27, 2016 Research and Markets ... America 2016-2020" report to their offering. ... North America to grow at a CAGR of 12.28% ... prepared based on an in-depth market analysis with inputs from industry ... over the coming years. The report also includes a discussion of ...
(Date:6/22/2016)... On Monday, the Department of Homeland Security (DHS) issued ... the Biometric Exit Program. The Request for Information (RFI), ... that CBP intends to add biometrics to confirm when ... , in order to deter visa overstays, to ... Logo - http://photos.prnewswire.com/prnh/20160622/382209LOGO ...
(Date:6/16/2016)... , June 16, 2016 ... is expected to reach USD 1.83 billion by ... View Research, Inc. Technological proliferation and increasing demand ... are expected to drive the market growth. ... The development of advanced multimodal techniques ...
Breaking Biology News(10 mins):
(Date:12/8/2016)... 8, 2016 Oxford ... erweitert seine Palette an anpassbaren SureSeq™ NGS-Panels mit ... Panels, das ein schnelles und kostengünstiges Studium der ... bietet eine Erkennung von Einzel-Nukleotid-Variationen (Single Nucleotide Variation, ... einzigen kleinen Panel und ermöglicht eine individuelle Anpassung ...
(Date:12/8/2016)... Dec. 8, 2016  Anaconda BioMed S.L., a pre-clinical ... the next generation neuro-thrombectomy system for the treatment of ... G. Jovin, MD to join its Scientific Advisory Board ... strategic network of scientific and clinical experts to Anaconda ... the ANCD BRAIN ® to its clinical phase. ...
(Date:12/8/2016)... Maryland (PRWEB) , ... December ... ... announces the commercial launch of flexible packaging for their exceptionally efficient ... disposable bag system extends RoosterBio’s portfolio of bioprocess media products engineered to ...
(Date:12/8/2016)... ... , ... This CAST literature review and report looks at problems caused by ... economic effects in countries that are major global commodity exporters and importers, which show ... of low level presence (LLP) puts large volumes of trade worth billions of dollars ...
Breaking Biology Technology: