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:8/28/2014)... mobile app called TX Invasives is now available from ... of Texas at Austin for identifying harmful non-native plant, ... species in the United States cause about $137 billion ... agricultural crops, clog waterways, kill native plants and more. ... app for reporting where invasive species occur, we,re more ...
(Date:8/28/2014)... to announce the selection of Dr. Fred Baxendale as ... those who have served ESA for at least 20 ... Society that has reached an extraordinary level. Candidates for ... and then voted on by the ESA membership. Dr. ... Entomology 2014, ESA,s Annual Meeting in Portland, Oregon this ...
(Date:8/28/2014)... bacterial culprits that may drive inflammatory bowel diseases (IBD) ... own intestinal immune responses as a guide. , The ... Cell . , Trillions of bacteria exist within the ... the development and progression of IBD. Yet it,s thought ... a person,s susceptibility to IBD and its potential severity. ...
Breaking Biology News(10 mins):Mobile app makes ID of harmful plants, insects in Texas a snap 2Fred Baxendale selected as Honorary Member of the Entomological Society of America 2Yale study identifies possible bacterial drivers of IBD 2
... processing fluidsIn an important advance toward the large-scale ... University have developed a new method of replacing ... with cheaper oils that are commonplace at industrial ... under the auspices of the Center for Biological ...
... conducted by a biologist at the University of California, San ... Animal Behaviour found that females of the species Uca crenulata ... their burrows before finally deciding on a mate. , “As ... sampling nearly as many candidates as the California fiddler crab,?said ...
... stem cells taken from bone marrow are the "shooting stars" ... the cells might be able to pass through the blood ... seen as the potential key to the treatment of certain ... University Clinic has produced some sobering findings: although the cells ...
Cached Biology News:The right drug at the right time 2The right drug at the right time 3Biologist Discovers What May Be World’s ‘Pickiest?Mates 2Biologist Discovers What May Be World’s ‘Pickiest?Mates 3Research casts doubt on circulating stem cells 2Research casts doubt on circulating stem cells 3
(Date:8/29/2014)... , Aug. 29, 2014 /PRNewswire/ - iCo ... ICOTF), today reported financial results for the six ... otherwise, are expressed in Canadian dollars and presented ... Second Quarter 2014 Highlights , Announced ... acuity (VA) primary endpoint for subjects enrolled in ...
(Date:8/29/2014)... (PRWEB) August 29, 2014 Local veterinarian, ... Veterinary Hospital are seeking candidates to participate in an ... osteoarthritis. The ultimate goal of this study is ... cells into one or two arthritically affected joints can ... , Candidates for the current investigational study must ...
(Date:8/29/2014)... Three Lawrence Livermore researchers have received ... R&D Award for their research in producing ... , Shared with collaborators from the National Renewable ... Las Vegas (UNLV), the award recognizes the team ... production and corrosion processes. , These models have ...
(Date:8/29/2014)... 2014 Due to a misstatement posted by ... Adult Stem Cell Technology Center, LLC ( ASCTC ) was ... therapy research that might benefit ALS patients. Because of ... stem cell technologies and therapeutic applications, FRC listed ASCTC as ... donors who wish not to support research that requires ...
Breaking Biology Technology:iCo Therapeutics Announces Second Quarter 2014 Financial Results 2iCo Therapeutics Announces Second Quarter 2014 Financial Results 3iCo Therapeutics Announces Second Quarter 2014 Financial Results 4Burnt Hills Veterinary Hospital Seeks Candidates for an Investigational Study of Stem Cells for Dogs with Arthritis 2Livermore Team Awarded for Hydrogen Production Research 2The Adult Stem Cell Technology Center, LLC Declines ALS Ice Bucket Challenge Donors Wishing to Support Ethical Research for New Stem Cell Therapies 2The Adult Stem Cell Technology Center, LLC Declines ALS Ice Bucket Challenge Donors Wishing to Support Ethical Research for New Stem Cell Therapies 3
... Make way for the real nanopod and make room ... with the U.S. Department of Energys Lawrence Berkeley National ... Berkeley have created the first fully functional radio from ... orders of magnitude the smallest radio ever made. , ...
... Senomyx, Inc. (Nasdaq:,SNMX), a leading company focused on ... ingredients for the packaged food and,beverage industry, announced ... Foods Global, Inc. will conclude on December 9,2007, ... term of the existing,agreement. The conclusion of this ...
... Oct. 31 Align,Technology, Inc. (Nasdaq: ALGN ... straightening teeth without wires or brackets, has been ... Silicon Valley, a,ranking of the fastest growing technology, ... by Deloitte & Touche USA LLP, one of,the ...
Cached Biology Technology:Make way for the real nanopod 2Make way for the real nanopod 3Make way for the real nanopod 4Senomyx Announces Conclusion of Discovery and Development Collaboration With Kraft Foods Global, Inc. 2Senomyx Announces Conclusion of Discovery and Development Collaboration With Kraft Foods Global, Inc. 3Align Technology, Inc. Ranked 23rd in Deloitte's Technology Fast 50 Program for Silicon Valley Scientific & Medical Equipment, and Bio-Technology Companies 2Align Technology, Inc. Ranked 23rd in Deloitte's Technology Fast 50 Program for Silicon Valley Scientific & Medical Equipment, and Bio-Technology Companies 3
This bispecific antibody complex has been tested for efficient depletion of CD41+ cells using the StemSep ; negative immunomagnetic cell separation system....
... it easy to supply microplates, deepwells, and ... operator convenience in mind, iLink incorporates multiple ... use. The iLink software is the key ... sub-assays, that can be copied and installed ...
No-Weigh Dithiothreitol (DTT) ,7.7 mg DTT/Tube x 48 tubes...
This kit is designed to select cells labeled with phycoerythrin- (PE-) conjugated antibodies. Kit includes reagents for labeling 3 x 10 9 cells and EasySep magnet....
Biology Products: