Navigation Links
Gerton Lab determines the composition of centromeric chromatin
Date:9/28/2009

The Stowers Institute's Gerton Lab has provided new evidence to clarify the structure of nucleosomes containing Cse4, a centromere-specific histone protein required for proper kinetochore function, which plays a critical role in the process of mitosis. The work, conducted in yeast cells, was published in the most recent issue of Molecular Cell.

The centromeric nucleosome acts as a guide for the position of the kinetochore. The kinetochore attaches the chromosome to a microtubule for chromosome segregation. It is essential that chromosome segregation is carried out with high fidelity, since errors in this process can produce cells which contain an abnormal number of chromosomes. In humans, these types of errors are hallmarks of many types of cancer, and therefore are thought to play a significant role in tumor formation, malignancy, and metastasis.

For many years, researchers assumed that centromeric nucleosomes were structurally like other nucleosomes "octamers" with two copies each of four different histone protein subunits with DNA wrapped around the outside. Recently, two alternative models for the structure of centromeric nucleosomes have been proposed. The first suggests that two of the histone protein pairs normally found in the centromere are replaced by the Scm3 protein, creating a hexameric nucleosome made up of six subunits. The second model suggested that centromeric nucleosomes contain a single molecule of each of the four proteins, forming a tetrameric structure called a hemisome.

The Gerton Lab provides evidence for a model in which Cse4-containing nucleosomes are, in fact, octamers. A variety of unbiased methods was used to test the three different models, including genetic, biochemical, and cell biological approaches. In the end, the octamer model was the only one consistent with all of the current experimental results.

"These data support a new model for the structure of centromeric nucleosomes and reinforce the importance of both structure and function of octameric nucleosomes in the epigenetic propagation of centromeric chromatin," said Raymond Camahort, Ph.D., formerly a Postdoctoral Research Associate and lead author on the paper. "In order to better understand how centromeric nucleosomes are formed, we must understand their composition. This work has answered a critical question of structure."

"Many lines of evidence indicate that centromeric chromatin is evolutionarily conserved from yeast to man," said Jennifer Gerton, Ph.D., Associate Investigator and senior author on the paper. "The octameric structure for centromeric nucleosomes may be universal. Our studies in budding yeast help to shed light on mechanisms of centromere propagation and chromosome transmission that are needed to maintain human health."


'/>"/>

Contact: Marie Jennings
mfj@stowers.org
816-926-4015
Stowers Institute for Medical Research
Source:Eurekalert

Related biology news :

1. Response to immune protein determines pathology of multiple sclerosis
2. Improved technique determines structure in membrane proteins
3. Diet prior to pregnancy determines sheeps gender
4. New technique determines the number of fat cells remains constant in all body types
5. Gene determines whether male body odor smells pleasant
6. Study of isolated snakes could help shed light on venom composition
7. Breastfeeding duration and weaning diet may shape childs body composition
8. Tree species composition influences nitrogen loss from forests
9. Climate change causing significant shift in composition of coastal fish communities
10. Lets talk -- new paradigms in the research of the biomolecular composition of water
11. Does the victim affect snake venom composition?
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:11/30/2016)... CHICAGO , Nov. 30, 2016  higi ... a new partnership initiative targeting national brands, industry ... and reward their respective audiences for taking steps ... Since its inception in 2012, higi has built ... US, impacting over 38 million people who have ...
(Date:11/24/2016)... -- Cercacor today introduced Ember TM Sport Premium ... measure hemoglobin, Oxygen Content, Oxygen Saturation, Perfusion Index, ... approximately 30 seconds. Smaller than a smartphone, using only ... key data about their bodies to help monitor these ... Hemoglobin carries oxygen to muscles. When hemoglobin and ...
(Date:11/17/2016)... Nov. 17, 2016 Global Market Watch: ... (Disease-Based Banks, Population-Based Banks and Academics) market is to witness ... Private Biobanks shows the highest Compounded Annual Growth Rate (CAGR) ... region during the analysis period 2014-2020. North America ... 9.95% followed by Europe at 9.56% ...
Breaking Biology News(10 mins):
(Date:12/2/2016)... ... , ... DrugDev believes the only way to achieve real change ... three tenets were on display at the 2nd Annual DrugDev User Summit (hosted by ... and site organizations to discuss innovation and the future of clinical research. , ...
(Date:12/2/2016)... ... December 02, 2016 , ... Robots will storm the Prudential Center in Boston, ... The event, which is held on the United Nations International Day of Persons with ... into the workplace. Suitable Technologies is partnering with NTI to showcase how technology can ...
(Date:12/2/2016)... leader in rapid infectious disease tests, introduced the Company,s newest product, the INSTI HIV ... http://photos.prnewswire.com/prnh/20161201/444905 ) Continue Reading ... ... , bioLytical was invited by the Clinton Health ... Self Test to 350 pharmacy representatives in Nairobi and Mombasa, ...
(Date:11/30/2016)... , November 30, 2016 ... a few players hold a dominant share in the ... River Laboratories International, Inc., and Merck KGaA, held a ... 2015. Transparency Market Research observes that these companies are ... on development products that are do not require rabbit ...
Breaking Biology Technology: