Navigation Links
Ticking of cellular clock promotes seismic changes in the chromatin landscape associated with aging
Date:10/3/2010

LA JOLLA, CA-Like cats, human cells have a finite number of lives-once they divide a certain number of times (thankfully, more than nine) they change shape, slow their pace, and eventually stop dividing, a phenomenon called "cellular senescence".

Biologists know that a cellular clock composed of structures at the chromosome end known as telomeres records how many "lives" a cell has expended. Up to now, investigators have not yet defined how the clock's ticking signals the approach of cellular oblivion.

In a study published in the Oct. 3, 2010, issue of Nature Structural and Molecular Biology, a team led by Jan Karlseder, Ph.D., at the Salk Institute for Biological Studies reports that as cells count down to senescence and telomeres wear down, their DNA undergoes massive changes in the way it is packaged. These changes likely trigger what we call "aging".

"Prior to this study we knew that telomeres get shorter and shorter as a cell divides and that when they reach a critical length, cells stop dividing or die," said Karlseder, an associate professor in the Molecular and Cell Biology Laboratory. "Something must translate the local signal at chromosome ends into a huge signal felt throughout the nucleus. But there was a big gap in between."

Karlseder and postdoctoral fellow Roddy O'Sullivan, Ph.D., began to close the gap by comparing levels of proteins called histones in young cells-cells that had divided 30 times-with "late middle-aged" cells, which had divided 75 times and were on the downward slide to senescence, which occurs at 85 divisions. Histone proteins bind linear DNA strands and compress them into nuclear complexes, collectively referred to as chromatin.

Karlseder and O'Sullivan found that aging cells simply made less histone protein than do young cells. "We were surprised to find that histone levels decreased as cells aged," said O'Sullivan, the study's first author. "These proteins are required th
'/>"/>

Contact: Gina Kirchweger
kirchweger@salk.edu
858-453-410-01340
Salk Institute
Source:Eurekalert  

Page: 1 2 3

Related biology news :

1. Pitt/Iowa team finds cellular structural molecule can be toxic: Makes pneumonia worse
2. UCI-Scripps study links cellular motors to memory
3. Mount Sinai researchers discover new mechanism behind cellular energy conversion
4. SSRIs may pack more punch at the cellular level than believed
5. An IRCM researcher pinpoints the cellular mechanism responsible for modulating the permeability of blood vessels
6. A cellular housekeeper, and potential target of obesity drugs, caught in action
7. Origins of multicellularity: All in the family
8. Biologists identify a new clue into cellular aging
9. Researchers demystifying complex cellular communications hubs found in sensory neurons
10. Intracellular express -- why transport protein molecules have brakes
11. Cellular mechanical forces may initiate angiogenesis
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Ticking of cellular clock promotes seismic changes in the chromatin landscape associated with aging
(Date:10/29/2014)... air pollutants released by unconventional oil and gas production ... published today in the open access journal Environmental ... formaldehyde were found. The study is the first to ... near production sites and could be used to supplement ... come from reserves that do not readily flow to ...
(Date:10/29/2014)... largest study of its kind to date, researchers have ... heighten the risk for autism. Joseph Buxbaum, Ph.D., Icahn ... Mark Daly, Ph.D., Broad Institute of Harvard and MIT, ... from affected children, parents and unrelated people. They identified ... to the risk for autism spectrum disorder (ASD) – ...
(Date:10/29/2014)... open for the Society of Interventional Radiology,s ... is the one place where interventional radiologists, ... care professionals can come together to find ... being presented, discussed and tested. , ... image-guided medicine, SIR 2015 will feature essential ...
Breaking Biology News(10 mins):Air quality and unconventional oil and gas sites 2Air quality and unconventional oil and gas sites 3SIR 2015: Interventional radiology shapes tomorrow's medicine 2
... the time, the immune system is the body,s protector, warding ... infection and disease. But in autoimmune diseases, the immune ... attacking normal cells. A major discovery by La Jolla ... previously unknown molecular interaction that is essential for T lymphocyte ...
... team of Russian veterinary colleagues and health experts from the ... distemper -- a virus afflicting domestic dogs and many wildlife ... tigers. The team presented its results at the first-ever ... Russian Far East city of Ussurisk. The symposium underscores ...
... stem cell therapies will be among the research topics ... on Cardiovascular Regenerative Medicine, which will be held Oct. ... into the state of the regenerative medicine field. ... Lung, and Blood Institute and the Foundation for the ...
Cached Biology News:La Jolla Institute discovers previously unknown cell interaction key in immune system attacks 2La Jolla Institute discovers previously unknown cell interaction key in immune system attacks 3Russian and US veterinarians collaborate to solve mysterious wild tiger deaths 2Russian and US veterinarians collaborate to solve mysterious wild tiger deaths 3NIH hosts Cardiovascular Regenerative Medicine Symposium Oct. 4-5 2
(Date:10/31/2014)... 30, 2014 The evening of ... decades-long heritage in successful medical device development to ... what it takes to successfully innovate in the ... of a two-hour on-site class, Insight gave master’s ... business, McCormick School of Engineering, medical and law ...
(Date:10/31/2014)... October 31, 2014 The report ... Rice), Formulation (Plain, Flavored, Sweetened, Unsweetened), Channel (Supermarket, ... Global Trends & Forecast to 2018," defines and ... analysis and forecast of revenue and volume for ... is projected to reach $14 Billion by 2018 ...
(Date:10/31/2014)... Oct. 31, 2014  Atlanta-based Intellimedix could make ... the onset of Ebola by suggesting a new, ... Georgia Tech,s Center for Computational Systems Biology have ... find alternative uses for existing drugs through systematic ... aid the bout against Ebola. ...
(Date:10/30/2014)... 30, 2014 2014 Deep Research ... is a professional and in-depth research report on ... Naltrexone HCL information, including its definition, classification, application, ... overview. This research covers the international market analysis, ... industry analysis covering macroeconomic environment & economic situation ...
Breaking Biology Technology:Insight Product Development Gives Northwestern University Students Foundation for Innovation Success 2Insight Product Development Gives Northwestern University Students Foundation for Innovation Success 3Dairy Alternative Beverage Market Projected to Reach $14 Billion by 2018 - Report by MarketsandMarkets 2Dairy Alternative Beverage Market Projected to Reach $14 Billion by 2018 - Report by MarketsandMarkets 3Dairy Alternative Beverage Market Projected to Reach $14 Billion by 2018 - Report by MarketsandMarkets 4Atlanta-Based Intellimedix May Help Solve Ebola With Computer Algorithms 2Naltrexone HCL Market & Nalbuphine HCL Industry Analysis for Global, China Regions Now at DeepResearchReports.com 2Naltrexone HCL Market & Nalbuphine HCL Industry Analysis for Global, China Regions Now at DeepResearchReports.com 3
... National Business Group on Health Names Leading Companies that Promote a ... ... The National Business,Group on Health (NBGH), a national non-profit organization of ... and promoting a healthy lifestyle for employees and their,families., GSK ...
... with Improved Usability & ... ... high incidence,of women,s health conditions that require intra-vaginal drug delivery and,the ... an alarming majority of women find their current treatment,options "unacceptable" or ...
... Germany, May 13 Caviar has become one ... view of the over fished,sturgeon populations in the ... sustainable aquaculture. United Food Technologies AG (UFT) has ... know-how in this sector.,This week, the company delivered ...
Cached Biology Technology:GlaxoSmithKline Named A Top Employer for Promoting Healthy Lifestyles 2GlaxoSmithKline Named A Top Employer for Promoting Healthy Lifestyles 3GlaxoSmithKline Named A Top Employer for Promoting Healthy Lifestyles 472% of Women Are Dissatisfied With Their Current Treatment of Vaginal Infection, Survey Finds 2Sturgeon and Caviar From Aquaculture: United Food Technologies AG Hands Over Turnkey Plant 2
... GeneMaths XT is undoubtedly the most complete ... advanced concept of layers and subsets makes ... layers for different data outputs, for example ... etc., as well as different subsets of ...
...
...
... several important steps of angiogenesis including proliferation, migration, ... reduces intracellular reactive oxygen species (ROS) level, H(2)O(2)-dependent ... Formula: ... MolWeight: 360.31484 Store ...
Biology Products: