Latest topics
» WHY DOES TONY PODESTA LOVE RED SHOES? ( PART ONE)
Today at 1:45 pm by PurpleSkyz

» #QAnon News - Q Drops/They React plus more
Today at 1:43 pm by PurpleSkyz

» Benjamin Fulford 8-20-18
Today at 1:37 pm by PurpleSkyz

» Lions, and Tigers, and Bears....and oh, my! World Trusts! By Anna Von Reitz plus more
Today at 1:30 pm by PurpleSkyz

» Sort of "freaked out" as it went by her! - Had never seen anything like it before... WEIRD
Today at 1:27 pm by terbo56

» Bridgette Lyn Dolgoff on Know Weigh Radio Show Host Dr. Lenny Thyme July 26, 2018 PT1-5
Today at 11:39 am by Consciousness Of Economic

» POOFness for AUG 19: RESPECT... SOMETHING GHOULKOWSKI KNOWS NOTHING ABOUT
Today at 11:38 am by PurpleSkyz

» Bridgette Lyn Dolgoff on Know Weigh Radio Show Host Dr. Lenny Thyme August 9,2018 PT1-5
Today at 11:36 am by Consciousness Of Economic

» Bridgette Lyn Dolgoff on Know Weigh Radio Show Host Dr. Lenny Thyme August 2, 2018 PT1-5
Today at 11:33 am by Consciousness Of Economic

» "QFS Oversight of all Banking Activities" by Ron Giles
Today at 11:32 am by PurpleSkyz

» Bridgette Lyn Dolgoff on Know Weigh Radio Show Host Dr. Lenny Thyme July 18, 2018 PT1-5
Today at 11:29 am by Consciousness Of Economic

» Isaac Kappy Drops More Names: Marilyn Manson, Tyler Shields
Today at 11:28 am by PurpleSkyz

» 4 Years After CDC Whistleblower Reveals Vaccine Fraud Still Nothing Happens
Today at 11:21 am by PurpleSkyz

» Three transparent Spheres with figures inside caught over Lake Okanagan, Canada
Today at 10:53 am by PurpleSkyz

» UFO News ~ Does this look like a conventional aircraft? plus MORE
Today at 10:51 am by PurpleSkyz

» Study Shows Cell Phone Towers Harmful To Animals, Plants – 5G Will Be Much Worse
Today at 10:48 am by PurpleSkyz

» MIND BLOWING PICS!!The Stripe Planet reveals itself!!
Today at 10:45 am by PurpleSkyz

» NIBIRU News ~ WORMWOOD STAR TRUTH plus MORE
Today at 10:43 am by PurpleSkyz

» Vaccines - Causing Psychological Disorders & Anorexia In Children - David Icke
Today at 10:40 am by PurpleSkyz

» Mars weapon and structure found in NASA rover photo
Today at 10:39 am by PurpleSkyz

» holistic doctor forced to close clinic after family and patients lives threatened
Today at 10:36 am by PurpleSkyz

» Dustification: North Tower Spire Turns to Dust
Today at 10:34 am by PurpleSkyz

» Doctor to the Queen fatally struck while biking to work
Today at 9:42 am by bs4ever

» SETH RICH NEW DEVELOPMENTS
Today at 9:24 am by Visionkeeper

» The Artificial Battle Between Mind and Machine Over the Future
Today at 12:36 am by MartyM

» Tiffany Fitzhenry 8-17-18… “Where We Go One We Go All”
Today at 12:26 am by PurpleSkyz

» Strange Sounds over Miami FL!
Today at 12:16 am by PurpleSkyz

» Odd Fireball '40 times as bright as full moon' lights up Alabama sky
Yesterday at 11:04 pm by PurpleSkyz

» Jerzy Babkowski (AKA ZAP) "The Prey Of The Predator"
Yesterday at 9:53 pm by PurpleSkyz


CLICK THE SUBSCRIBE BUTTON BELOW TO RECEIVE OUR DAILY NEWSLETTER

A 2ND EMAIL COMPLETES THE ACTIVATION PROCESS




CLICK THE PURPLE BUTTON TO VIEW OUR LATEST POSTS



You are not connected. Please login or register

Out Of Mind » THE INSANITY OF REALITY » SCIENCE » Parasitic DNA proliferates in aging tissues

Parasitic DNA proliferates in aging tissues

Go down  Message [Page 1 of 1]

1 Parasitic DNA proliferates in aging tissues on Fri Dec 20, 2013 11:56 pm

PurpleSkyz

avatar
Admin
Parasitic DNA proliferates in aging tissues
Posted by Xeno on December 21, 2013
The genomes of organisms from humans to corn are replete with “parasitic” strands of DNA that, when not suppressed, copy themselves and spread throughout the genome, potentially affecting health. Earlier this year Brown University researchers found that these “retrotransposable elements” were increasingly able to break free of the genome’s control in cultures of human cells. Now in a new paper in the journal Aging, they show that RTEs are increasingly able to break free and copy themselves in the tissues of mice as the animals aged. In further experiments the biologists showed that this activity was readily apparent in cancerous tumors, but that it also could be reduced by restricting calories.
“As mice age we are seeing deregulation of these elements and they begin to be expressed and increase in copy number in the genome,” said Jill Kreiling, a research assistant professor at Brown, and leader of the study published in advance online Dec. 7. “This may be a very important mechanism in leading to genome instability. A lot of the chronic diseases associated with aging, such as cancer, have been associated with genome instability.”
Whether the proliferation of RTEs is exclusively a bad thing remains a hot question among scientists, but what they do know is that the genome tries to control RTEs by wrapping them up in a tightly wound configuration called heterochromatin. In their experiments, Kreiling and co-corresponding author Professor John Sedivy found that overall, the genomes of several mouse tissues become more heterochromatic with age. But they also found, paradoxically, that some regions where RTEs are concentrated became – loosened up instead , particularly after mice reached the 2-year mark (equivalent to about the 70-year mark for a person).
An important advance in this paper compared to the prior work in cell cultures, Sedivy said, is that the researchers were able to show the loosening of control over RTEs was associated with the chronological aging of the whole organism and specific tissues. Before in cell culture the aging they tracked was based on the number of times individual cells were able to divide. That kind of cellular aging is called “replicative senescence” and is believed to be rare in many normal tissues.
“This brings home the magnitude of the problem,” Sedivy said. “We looked in some pretty major tissues. This appears to be a much more widespread phenomenon. The observation that RTEs become activated with chronological aging of mouse tissues also brings this research in close alignment with very similar discoveries using the fruit fly Drosophila in the labs of Brown Professors Stephen Helfand and Robert Reenan,. The remarkable evolutionary conservation of these fundamental molecular processes indicates that they are likely important aspects of aging. “
In the new research, the team including lead author Marco DeCecco looked at cells from the liver and skeletal muscle of mice at ages 5, 24 and 36 months. Comparing gene expression and DNA sequences from the cells, they found elevated expression in both tissues of many RTEs after 24 months. Not only were the RTEs expressed more, but also they succeeded in copying themselves and showing up elsewhere in the genome. For example, an RTE named “MusD” became more than twice as abundant in liver tissue between the ages 24 and 36 months.
The RTEs were considerably less successful in proliferating, however, in mice who were still adequately nourished, but fed 40 percent fewer calories than mice fed a standard diet. Calorie restriction has been widely shown to mitigate many consequences of aging in different animal models.
On the other hand, the researchers found that several RTEs were much more abundant in mouse tissues affected by naturally occurring cancers, such as lymphoma and hepatocellular carcinoma.
The research does not yet provide evidence that RTEs have a causal role in cancer, Sedivy said. For the time being it’s only an association. But he said that researchers have a path forward to study the health consequences of the RTE proliferation that apparently occurs in aging. Certain drugs can inhibit RTE proliferation so researchers should be able to see if doing so extends the amount of time an animal is healthy and free of chronic disease in future mouse experiments.
via Parasitic DNA proliferates in aging tissues.


Thanks to: http://xenophilius.wordpress.com




  

Back to top  Message [Page 1 of 1]

Permissions in this forum:
You cannot reply to topics in this forum