Aging cells unravel their DNA

Dec 16, 2013
Satellite DNA (green) is compact in a normal proliferative cell (left) but distended in a nonproliferative senescent cell (right). A study in The Journal of Cell Biology identifies a common marker of senescence that could have important implications for aging and cancer. Credit: Swanson et al., 2013

Senescent cells, which are metabolically active but no longer capable of dividing, contribute to aging, and senescence is a key mechanism for preventing the spread of cancer cells. A study in The Journal of Cell Biology identifies a common, early marker of senescent cells that could have important implications for tumor suppression and aging-related diseases like Progeria.

Senescent cells permanently exit the cell cycle, a process that can be triggered by the cellular changes associated with aging or by other stresses such as the expression of cancer-promoting oncogenes. Despite the importance of senescence for both aging and , however, researchers have failed to identify any distinguishing features that are common to all types of .

Researchers from UMass Medical School discovered that the satellite DNA found at human and mouse centromeres—the points where chromosomes connect to microtubules during cell division—unraveled from its normal compact state as cells entered senescence. This unraveling—which the researchers termed senescence-associated distension of satellites, or SADS—occurred regardless of how senescence was induced and appeared to occur early in the process of cell cycle exit. Strikingly, cells from Progeria patients formed SADS as they exited the , suggesting that these prematurely arrested cells follow the same senescence pathway as normally aging cells.

This video is not supported by your browser at this time.
Satellite DNA (green and red) is compact in a normal proliferative cell (left) but distended in a nonproliferative senescent cell (right). A study in The Journal of Cell Biology identifies a common, early marker of senescence that may have important implications for aging and cancer. Credit: Swanson et al., 2013

The extensive unfolding of structures critical for cell division could thus prove key to inhibiting cell proliferation, in the context of both aging and limiting the proliferation of tumor cells.

Explore further: How do our muscles work? Scientists reveal important new insights into muscle protein

More information: Swanson, E.C., et al. 2013. J. Cell Biol. DOI: 10.1083/jcb.201306073

add to favorites email to friend print save as pdf

Related Stories

Tipping the balance between senescence and proliferation

Nov 15, 2013

An arrest in cell proliferation, also referred to as cellular senescence, occurs as a natural result of aging and in response to cellular stress. Senescent cells accumulate with age and are associated with many aging phenotypes, ...

Study discovers that stem cell senescence drives aging

Apr 18, 2013

Declining levels of the protein BubR1 occur when both people and animals age, and contribute to cell senescence or deterioration, weight loss, muscle wasting and cataracts. Mayo Clinic researchers have shown that adult progenitor ...

Cell senescence does not stop tumor growth

Jan 19, 2012

Since cancer cells grow indefinitely, it is commonly believed that senescence could act as a barrier against tumor growth and potentially be used as a way to treat cancer. A collaboration between a cancer biologist from the ...

Recommended for you

Genomes of malaria-carrying mosquitoes sequenced

7 hours ago

Nora Besansky, O'Hara Professor of Biological Sciences at the University of Notre Dame and a member of the University's Eck Institute for Global Health, has led an international team of scientists in sequencing ...

How calcium regulates mitochondrial carrier proteins

Nov 26, 2014

Mitochondrial carriers are a family of proteins that play the key role of transporting a chemically diverse range of molecules across the inner mitochondrial membrane. Mitochondrial aspartate/glutamate carriers are part of ...

Team conducts unprecedented analysis of microbial ecosystem

Nov 26, 2014

An international team of scientists from the Translational Genomics Research Institute (TGen) and The Luxembourg Centre for Systems Biomedicine (LCSB) have completed a first-of-its-kind microbial analysis of a biological ...

Students create microbe to weaken superbug

Nov 25, 2014

A team of undergraduate students from the University of Waterloo have designed a synthetic organism that may one day help doctors treat MRSA, an antibiotic-resistant superbug.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.