Featured Research

from universities, journals, and other organizations

Centromeres Cross Over, A Lot

Date:
June 17, 2008
Source:
Rockefeller University Press
Summary:
Recombination at centromeres is higher than anywhere else on the chromosome, even though methyltransferases do their best to prevent it, according to new research. Centromeric recombination has been hard to study because the DNA at centromeres is so repetitive -- it's hard to see when a segment has switched chromatids.

Recombination at centromeres is higher than anywhere else on the chromosome, even though methyltransferases do their best to prevent it, according to a new study.

Centromeric recombination has been hard to study because the DNA at centromeres is so repetitive--it's hard to see when a segment has switched chromatids. Jaco et al. have now addressed this challenge by using CO-FISH (chromosome orientation fluorescence in situ hybridization). After replication, the two new strands are digested away, leaving the two old strands. Because the strands are complementary in sequence, they can be tagged with strand-specific fluorescent probes. Using just one probe, only one chromatid would show a signal if no recombination had occurred.

Instead, the authors found that both chromatids fluoresced. And not just at one point--on average, the authors counted, centromeres had undergone 15 recombination events. This is about six times the rate of recombination as that seen for an equal length of telomeric DNA, and 175 times the rate for genomic DNA as a whole.

Telomeric recombination is inhibited by protein complexes called shelterins and by DNA methylation. The centromere has no shelterin, but it is methylated. Knockdown of DNA methyltransferases increased recombination at the centromere by about 50%, and decreased centromere length, possibly because of misalignment between repeated segments during recombination, a common problem with repetitive DNA. How methylation limits recombination, and why centromeres didn't lengthen as well as shorten, are unknown.

Their repetitive structure makes centromeres recombinogenic by nature, and the authors suggest that epigenetic regulation may ensure the continued stability of essential binding regions for proteins that link to the centromere.


Story Source:

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


Journal Reference:

  1. Jaco, I., et al. Centromeres cross over, a lot. The Journal of Cell Biology, June 9, 2008 DOI: 10.1083/jcb.1816iti5

Cite This Page:

Rockefeller University Press. "Centromeres Cross Over, A Lot." ScienceDaily. ScienceDaily, 17 June 2008. <www.sciencedaily.com/releases/2008/06/080612125029.htm>.
Rockefeller University Press. (2008, June 17). Centromeres Cross Over, A Lot. ScienceDaily. Retrieved April 20, 2014 from www.sciencedaily.com/releases/2008/06/080612125029.htm
Rockefeller University Press. "Centromeres Cross Over, A Lot." ScienceDaily. www.sciencedaily.com/releases/2008/06/080612125029.htm (accessed April 20, 2014).

Share This



More Plants & Animals News

Sunday, April 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Mich. Boy Unearths 10,000-Year-Old Mastodon Tooth

Mich. Boy Unearths 10,000-Year-Old Mastodon Tooth

Newsy (Apr. 20, 2014) A 9-year-old Michigan boy was exploring a creek when he came across a 10,000-year-old tooth from a prehistoric mastodon. Video provided by Newsy
Powered by NewsLook.com
Vermont Goat Meat Gives Refugees Taste of Home

Vermont Goat Meat Gives Refugees Taste of Home

AP (Apr. 18, 2014) Dairy farmers and ethnic groups in Vermont are both benefiting from a unique collaborative effort that's feeding a growing need for fresh and affordable goat meat. (April 18) Video provided by AP
Powered by NewsLook.com
Man Claims He Found Loch Ness Monster With... Apple Maps?

Man Claims He Found Loch Ness Monster With... Apple Maps?

Newsy (Apr. 18, 2014) Andy Dixon showed the Daily Mail a screenshot of what he believes to be the mythical beast swimming just below the lake's surface. Video provided by Newsy
Powered by NewsLook.com
First Ever 'Female Penis' Discovered In Animal Kingdom

First Ever 'Female Penis' Discovered In Animal Kingdom

Newsy (Apr. 18, 2014) Not only are these newly discovered bugs' sex organs reversed, but they also mate for up to 70 hours. Video provided by Newsy
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