Featured Research

from universities, journals, and other organizations

A protein required for integrity of induced pluripotent stem cells

Date:
April 21, 2014
Source:
Centro Nacional de Investigaciones Oncologicas (CNIO)
Summary:
The SIRT1 protein is needed to lengthen and maintain telomeres during cell reprogramming, new research demonstrates. SIRT1 also guarantees the integrity of the genome of stem cells that come out of the cell reprogramming process; these cells are known as induced pluripotent stem cells. The study sheds light on how cell reprogramming guarantees the healthy functioning of stem cells. This knowledge will help to overcome barriers that come out of the use of iPS cells so they may be used in regenerative medicine.

This image shows chromosome abnormalities in reprogrammed cells in which SIRT1 protein has been removed (in red).
Credit: Centro Nacional de Investigaciones Oncologicas

Cell reprogramming converts specialised cells such as nerve cells or skin cells towards an embryonic stem cell state. This reversal in the evolutionary development of cells also requires a reversal in the biology of telomeres, the structures that protect the ends of chromosomes; whilst under normal conditions telomeres shorten over time, during cell reprogramming they follow the opposite strategy and increase in length.

A study published today in the journal Stem Cell Reports, from the Cell Publishing Group, reveals that the SIRT1 protein is needed to lengthen and maintain telomeres during cell reprogramming. SIRT1 also guarantees the integrity of the genome of stem cells that come out of the cell reprogramming process; these cells are known as iPS cells (induced Pluripotent Stem cells).

The study has been carried out by the Spanish National Cancer Research Centre's Telomeres and Telomerase Group, in collaboration with the CNIO's Transgenic Mice Core Unit.

Since the Japanese scientist Shinya Yamanaka first obtained iPS cells from adult tissue in 2006, regenerative medicine has become one of the most exciting and rapidly developing fields in biomedicine. There is a very ambitious aim, given the ability to differentiate iPS cells into any type of cell; this would allow for the regeneration of organs damaged by diseases such as Alzheimer, diabetes or cardiovascular diseases.

The nature of iPS cells however is causing intense debate. The latest research shows that chromosome aberrations and DNA damage can accumulate in these cells. "The problem is that we don't know if these cells are really safe," says María Luigia De Bonis, a postdoctoral researcher of the Telomeres and Telomerase Group who has done a large part of the work.

In 2009, the same CNIO laboratory discovered that telomeres increase in length during cell reprogramming (Marion et al., Cell Stem Cell, 2009); this increase is important as it allows stem cells to acquire the immortality that characterises them.

One year later, it was demonstrated that the levels of SIRT1 -- a protein belonging to the sirtuin family and that is involved in the maintenance of telomeres, genomic stability and DNA damage response -- are increased in embryonic stem cells. The question CNIO researchers asked was: is SIRT1 involved in cell reprogramming?

SAFER STEM CELLS

Employing mouse models and cell cultures as research tools in which SIRT1 had been removed, the team has discovered that this protein is necessary for reprogramming to occur correctly and safely."We observed cell reprogramming in the absence of SIRT1, but over time the produced iPS cells lengthen telomeres less efficiently and suffer from chromosome aberrations and DNA damage," says De Bonis. "SIRT1 helps iPS cells to remain healthy," she concludes.

The authors describe how this protective effect on iPS cells is, in part, mediated by the cMYC regulator. SIRT1 slows the degradationof cMYC, which results in an increase in telomerase (the enzyme that increases telomere length) in cells.

The study sheds light on how cell reprogramming guarantees the healthy functioning of stem cells. This knowledge will help to overcome barriers that come out of the use of iPS cells so they may be used in regenerative medicine.


Story Source:

The above story is based on materials provided by Centro Nacional de Investigaciones Oncologicas (CNIO). Note: Materials may be edited for content and length.


Journal Reference:

  1. Maria Luigia De Bonis, Sagrario Ortega, Maria A. Blasco. SIRT1 Is Necessary for Proficient Telomere Elongation and Genomic Stability of Induced Pluripotent Stem Cells. Stem Cell Reports, 2014; DOI: 10.1016/j.stemcr.2014.03.002

Cite This Page:

Centro Nacional de Investigaciones Oncologicas (CNIO). "A protein required for integrity of induced pluripotent stem cells." ScienceDaily. ScienceDaily, 21 April 2014. <www.sciencedaily.com/releases/2014/04/140421093929.htm>.
Centro Nacional de Investigaciones Oncologicas (CNIO). (2014, April 21). A protein required for integrity of induced pluripotent stem cells. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2014/04/140421093929.htm
Centro Nacional de Investigaciones Oncologicas (CNIO). "A protein required for integrity of induced pluripotent stem cells." ScienceDaily. www.sciencedaily.com/releases/2014/04/140421093929.htm (accessed July 23, 2014).

Share This




More Health & Medicine News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Courts Conflicted Over Healthcare Law

Courts Conflicted Over Healthcare Law

AP (July 22, 2014) — Two federal appeals courts issued conflicting rulings Tuesday on the legality of the federally-run healthcare exchange that operates in 36 states. (July 22) Video provided by AP
Powered by NewsLook.com
Why Do People Believe We Only Use 10 Percent Of Our Brains?

Why Do People Believe We Only Use 10 Percent Of Our Brains?

Newsy (July 22, 2014) — The new sci-fi thriller "Lucy" is making people question whether we really use all our brainpower. But, as scientists have insisted for years, we do. Video provided by Newsy
Powered by NewsLook.com
Scientists Find New Way To Make Human Platelets

Scientists Find New Way To Make Human Platelets

Newsy (July 22, 2014) — Boston scientists have discovered a new way to create fully functioning human platelets using a bioreactor and human stem cells. Video provided by Newsy
Powered by NewsLook.com
Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

TheStreet (July 21, 2014) — New research shows Gilead Science's drug Sovaldi helps in curing hepatitis C in those who suffer from HIV. In a medical study, the combination of Gilead's Hep C drug with anti-viral drug Ribavirin cured 76% of HIV-positive patients suffering from the most common hepatitis C strain. Hepatitis C and related complications have been a top cause of death in HIV-positive patients. Typical medication used to treat the disease, including interferon proteins, tended to react badly with HIV drugs. However, Sovaldi's %1,000-a-pill price tag could limit the number of patients able to access the treatment. TheStreet's Keris Lahiff reports from New York. Video provided by TheStreet
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins