Navigation Links
NIA researchers find gene to explain mouse embryonic stem cell immortality

Researchers at the National Institute on Aging (NIA), part of the National Institutes of Health, have discovered a key to embryonic stem (ES) cell rejuvenation in a geneZscan4as reported in the March 24, 2010, online issue of Nature. This breakthrough finding could have major implications for aging research, stem cell biology, regenerative medicine and cancer biology.

ES cells are unique because, along with the ability to develop into nearly any type of cell in the body, they can produce infinite generations of new, fully operational ES cells (daughter cells). ES cells are essentially immortal, meaning that they can divide indefinitely to produce additional generations of functional ES daughter cells. Other cells can only produce a certain number of generations of daughter cells before they no longer function properly. This is partially because the telomere, the protective end of the chromosome which carries the cell's genetic information, shortens each time a cell divides. When a telomere becomes too short, it can no longer protect the cell. At that time, the cell dies, turns itself off, known as cell senescence, or produces abnormal and possibly dysfunctional cells.

Until now, the mechanism for the ES cell's immortality had been a mystery. The prevailing theory was that ES cells practiced "self-renewal," meaning that when they divided, they produced daughter cells that were completely unaltered (including telomere length) from the parent. NIA researchers discovered that the process occurring in ES cells can be more appropriately described as "rejuvenation" than the "self-renewal." As in other cells, when ES cells replicate, the daughter cells are not identical to the parent and the telomeres are shorter. However, ES cells express a unique Zscan4 gene that, when activated (or turned on), rejuvenates the ES cell, restoring it to its original vigor. This rejuvenation includes telomere lengthening through recombination, when a shorter telomere combines with a longer telomere to elongate itself. Zscan4 then turns off. The gene is not turned on every time that the cell replicatesapproximately 5 percent of the cells will have an activated gene at any one point. The process is a cycle of cell replication (with telomere shortening) and intermittent activation of Zscan4 (cell rejuvenation).

Researchers are currently investigating whether a similar mechanism also operates in human cells.


Contact: Megan Homer
NIH/National Institute on Aging

Related medicine news :

1. Researchers discover fundamental step in immune-system development
2. Scott & White Healthcare researchers studying investigational agent that targets breast cancer
3. SRI International Researchers to Present Work on Early Detection Tool for Neglected Tropical Diseases at 2010 American Chemical Society (ACS) Meeting
4. Researchers find new chemotherapy combination shows promise in endometrial cancer
5. Researchers ID brain abnormalities in children exposed to methamphetamine in utero
6. Mount Sinai researchers are the first to identify heart abnormalities in World Trade Center workers
7. Researchers discover chemical that may protect hearts of muscular dystrophy patients
8. Researchers recommend curriculum on unhealthy substance use
9. Using new approach, Mayo Clinic researchers find level of gene alters risk of Alzheimers disease
10. Researchers discover brain tumors grow-or-go switch
11. Exposure to BPA may cause permanent fertility defects, Yale researchers find
Post Your Comments:
(Date:6/25/2016)... ... , ... The temporary closing of Bruton Memorial Library on June 21 due to a possible ... often overlooked aspect of head lice: the parasite’s ability to live away from a human ... but a necessary one in the event that lice have simply gotten out of control. ...
(Date:6/25/2016)... (PRWEB) , ... June 25, 2016 , ... On Friday, ... presented a Bronze Wellness at Work award to iHire in recognition of their exemplary ... part of the 7th annual Maryland Workplace Health & Wellness Symposium at the BWI ...
(Date:6/24/2016)... ... June 24, 2016 , ... Marcy was in a crisis. Her son James, eight, was out ... family verbally and physically. , “When something upset him, he couldn’t control his emotions,” remembers ... would throw rocks at my other children and say he was going to kill them. ...
(Date:6/24/2016)... NY (PRWEB) , ... June 24, 2016 , ... Topical BioMedics, Inc, makers of Topricin ... companies that call for a minimum wage raise to $12 an hour by 2020 and ... This will restore the lost value of the minimum wage, assure the wage floor does ...
(Date:6/24/2016)... ... 2016 , ... Strategic Capital Partners, LLC (SCP) in concert ... capital for emerging technology companies. SCP has delivered investment events and professional ... than a million dollars of capital investment for five companies. The ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... June 24, 2016  Collagen Matrix, Inc., ("Collagen ... and manufacturing of collagen and mineral based medical ... that Bill Messer has joined the ... further leverage the growing portfolio of oral surgery, ... Bill joins the Collagen Matrix executive team ...
(Date:6/24/2016)... 24, 2016 The Academy of Managed Care ... that would allow biopharmaceutical companies to more easily ... make formulary and coverage decisions, a move that addresses ... medicines. The recommendations address restrictions in the ... the drug label, a prohibition that hinders decision makers ...
(Date:6/24/2016)... , June 24, 2016   Pulmatrix, Inc ., ... developing innovative inhaled drugs, announced today that it was ... Investments reconstituted its comprehensive set of U.S. and ... "This is an important milestone for Pulmatrix," said Chief ... shareholder awareness of our progress in developing drugs for ...
Breaking Medicine Technology: