Featured Research

from universities, journals, and other organizations

Discovery of DNA silencing mechanism reveals how plants protect their genome

Date:
May 13, 2011
Source:
RIKEN
Summary:
Researchers in Japan have clarified a key epigenetic mechanism by which an enzyme in the model plant Arabidopsis protects cells from harmful DNA elements. The finding contributes to advancing our understanding of a broad range of biological processes in both plants and animals, opening the door to applications in cancer therapy and agriculture.

Researchers at the RIKEN Plant Science Center (PSC) have clarified a key epigenetic mechanism by which an enzyme in the model plant Arabidopsis protects cells from harmful DNA elements. Published in the online journal PLoS Genetics, the finding contributes to advancing our understanding of a broad range of biological processes in both plants and animals, opening the door to applications in cancer therapy and agriculture.

In everything from protein synthesis to gene expression to development, living cells depend critically for their survival on the successful functioning of their DNA. Certain DNA elements such as transposons, fragments of DNA that replicate within an organism's genome, can however disrupt this functioning and disable genes. To defend against such harmful elements, eukaryotic cells form inactive tightly-packed DNA called heterochromatin, whose dense structure serves to repress ("silence") the expression of nearby gene sequences and protect the genome.

Earlier research identified the enzyme HDA6 as playing a key role in such "hetrochromatin silencing" in the model plant Arabidopsis, but the mechanism involved remained unclear. In order to clarify this mechanism, the research group investigated the involvement of HDA6 in two processes: DNA methylation, an epigenetic modification that changes the structure of DNA without altering its sequence, and the modification of histone, the main component of chromatin.

Through a genome-wide comparison, the researchers were able to show that plants with repressed HDA6 function are not able to silence harmful DNA elements, suggesting that the enzyme plays an important role in gene silencing. Further investigation revealed that HDA6 binds directly to transposons and silences their activity through specific histone modifications, and that another enzyme, the DNA methyltransferase MET1, cooperates with HDA6 in this gene silencing.

Together, the findings establish for the first time that MET1-mediated DNA methylation and HDA6-mediated histone modification work together in repressing harmful DNA elements. By shedding light on the complex interplay between these two processes, the findings provide valuable insight on how plants and animals have evolved to protect their genome from harmful DNA, contributing to applications in areas such as cancer therapy and agriculture.


Story Source:

The above story is based on materials provided by RIKEN. Note: Materials may be edited for content and length.


Journal Reference:

  1. Taiko Kim To, Jong-Myong Kim, Akihiro Matsui, Yukio Kurihara, Taeko Morosawa, Junko Ishida, Maho Tanaka, Takaho Endo, Tetsuji Kakutani, Tetsuro Toyoda, Hiroshi Kimura, Shigeyuki Yokoyama, Kazuo Shinozaki, Motoaki Seki. Arabidopsis HDA6 Regulates Locus-Directed Heterochromatin Silencing in Cooperation with MET1. PLoS Genetics, 2011; 7 (4): e1002055 DOI: 10.1371/journal.pgen.1002055

Cite This Page:

RIKEN. "Discovery of DNA silencing mechanism reveals how plants protect their genome." ScienceDaily. ScienceDaily, 13 May 2011. <www.sciencedaily.com/releases/2011/05/110512082935.htm>.
RIKEN. (2011, May 13). Discovery of DNA silencing mechanism reveals how plants protect their genome. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2011/05/110512082935.htm
RIKEN. "Discovery of DNA silencing mechanism reveals how plants protect their genome." ScienceDaily. www.sciencedaily.com/releases/2011/05/110512082935.htm (accessed July 31, 2014).

Share This




More Plants & Animals News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Visitors Feel Part of the Pack at Wolf Preserve

Visitors Feel Part of the Pack at Wolf Preserve

AP (July 31, 2014) — Seacrest Wolf Preserve on the northern Florida panhandle allows more than 10,000 visitors each year to get up close and personal with Arctic and British Columbian Wolves. (July 31) Video provided by AP
Powered by NewsLook.com
Florida Panther Rebound Upsets Ranchers

Florida Panther Rebound Upsets Ranchers

AP (July 31, 2014) — With Florida's panther population rebounding, some ranchers complain the protected predators are once again killing their calves. (July 31) Video provided by AP
Powered by NewsLook.com
Dangerous Bacteria Kills One in Florida

Dangerous Bacteria Kills One in Florida

AP (July 31, 2014) — Sarasota County, Florida health officials have issued a warning against eating raw oysters and exposing open wounds to coastal and inland waters after a dangerous bacteria killed one person and made another sick. (July 31) Video provided by AP
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) — Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
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