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:3/2/2017)... -- Who risk to be deprived of its imprint ... https://www.reportbuyer.com/product/4313699/ WILL APPLE AND SAMSUNG CONFRONT ... sensors using capacitive technology represent a fast growing market, ... an increase of 360% of the number of fingerprint ... sensor market between 2014 and 2017 (source : N+1 ...
(Date:2/28/2017)... LOS ANGELES , Feb. 28, 2017   ... identity verification software globally, announces significant enhancements to new ... in May 2016. New products include mobile and desktop ... and DocX TM - a real time manual ... Acuant,s core idScan® technology provides the fastest and most ...
(Date:2/27/2017)... 2017   Strategic Cyber Ventures , the industry,s ... a $3.5 million investment in  Polarity , the first ... is DC based and is led by cybersecurity veterans ... Ron Gula , also a longtime cybersecurity veteran ... this series A round of funding. This new funding ...
Breaking Biology News(10 mins):
(Date:3/23/2017)... , March 23, 2017 Kineta, Inc., ... of novel therapies in immuno-oncology, today announced the ... small molecule compounds that activate interferon response factor ... and demonstrate immune-mediated tumor regression in a murine ... study who demonstrated complete tumor regression to initial ...
(Date:3/23/2017)... (PRWEB) , ... March 23, 2017 , ... ... monitoring solutions, today announced the hire of Dr. Sigmund “Sig” Floyd as Vice ... applications, strategic partnerships and joint development activities. , “Dr. Floyd’s career has spanned ...
(Date:3/22/2017)... -- Good Start Genetics, a leading family genomics company, ... covered lives mark through its most recent payor addition, ... . With newly signed contracts nationally and others in ... acceptance based on the quality of its science, the ... industry-leading customer care and support and its published cost-effectiveness ...
(Date:3/22/2017)... , March 22, 2017 /PRNewswire/ - FACIT ... (the "Company" or "Propellon"), a start-up created by ... anti-cancer therapeutics. FACIT,s investment, combined with non-dilutive capital, ... program. The seed funding enables Propellon to accelerate ... the Company for financing and/or entering a strategic ...
Breaking Biology Technology: