Navigation Links
Centromeres cross over, a lot
Date:6/12/2008

Recombination at centromeres is higher than anywhere else on the chromosome, even though methyltransferases do their best to prevent it, say Jaco et al., as published in the June 16 issue of the Journal of Cell Biology.

Centromeric recombination has been hard to study because the DNA at centromeres is so repetitiveit'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 pointon 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.


'/>"/>

Contact: Emma Hill
ehill@rockefeller.edu
212-327-8011
Rockefeller University Press
Source:Eurekalert

Page: 1

Related biology news :

1. Energy Crossroads conference April 30 and May 1 at Stanford University
2. Scientists find a fingerprint of evolution across the human genome
3. Shilatifard Lab sheds light on molecular machinery required for translation of histone crosstalk
4. Gene study supports single main migration across Bering Strait
5. A mechanism to explain biological cross-talk between 24-hour body cycle and metabolism
6. Research sheds new light on how diseases jump across species
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/2/2016)... , December 1, 2016 ... type (Fingerprint, Voice), Future Technology (Iris Recognition System), ... Region - Global Forecast to 2021", published by ... 442.7 Million in 2016, and is projected to ... a CAGR of 14.06%.      (Logo: ...
(Date:11/29/2016)... 2016 BioDirection, a privately held medical device ... objective detection of concussion and other traumatic brain injury ... a meeting with the U.S. Food and Drug Administration ... Package. During the meeting company representatives reviewed plans for ... to commencement of a planned pilot trial. ...
(Date:11/24/2016)... Calif. , Nov. 23, 2016 Cercacor ... endurance athletes and their trainers non-invasively measure ... Index, Pulse Rate, and Respiration Rate in approximately 30 ... enables users easy and immediate access to key data ... part of a training regimen. Hemoglobin ...
Breaking Biology News(10 mins):
(Date:12/4/2016)... (PRWEB) , ... December 03, 2016 , ... ... ground-breaking microbiome studies. A microbiome impact grant award has been made to Dr. ... of heavy smoking and drinking on the oral microbiome. Grant proposals have been ...
(Date:12/2/2016)... ... December 02, 2016 , ... In anticipation ... and lumbar disc production, company President, Jake Lubinski will be traveling to Switzerland ... AxioMed disc in Bern, Lucerne, and Zurich to discuss the benefits of a ...
(Date:12/2/2016)... 2, 2016 Amgen (NASDAQ: AMGN ) ... the submission of a Marketing Authorization Application (MAA) to the ... to Avastin ® (bevacizumab). The companies believe this submission ... "The submission of ABP 215 to the ... our oncology portfolio," said Sean E. Harper , M.D., ...
(Date:12/2/2016)... ... 2016 , ... ACEA Biosciences, Inc. announced today that it will be presenting ... the World Conference on Lung Cancer 2016, taking place in Vienna, Austria December 3rd-8th. ... trials for AC0010 in patients with advanced non-small cell lung cancer harboring the EGFR ...
Breaking Biology Technology: