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:5/3/2016)... VILNIUS, Lithuania , May 3, 2016 /PRNewswire/ ... today released the MegaMatcher Automated Biometric Identification ... deployment of large-scale multi-biometric projects. MegaMatcher ABIS can ... and accuracy using any combination of fingerprint, face ... of MegaMatcher SDK and MegaMatcher ...
(Date:4/26/2016)... , April 27, 2016 ... the  "Global Multi-modal Biometrics Market 2016-2020"  report to ... ) , The analysts forecast the ... CAGR of 15.49% during the period 2016-2020.  ... number of sectors such as the healthcare, BFSI, ...
(Date:4/14/2016)... 14, 2016 BioCatch ™, ... today announced the appointment of Eyal Goldwerger ... Goldwerger,s leadership appointment comes at a time ... the deployment of its platform at several of the ... which discerns unique cognitive and physiological factors, is a ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... 2016 , ... Cancer experts from Austria, Hungary, Switzerland, and ... new and helpful biomarker for malignant pleural mesothelioma. Surviving Mesothelioma has just published ... , Biomarkers are components in the blood, tissue or body fluids that ...
(Date:6/27/2016)... , June 27, 2016  Liquid Biotech ... announced the funding of a Sponsored Research Agreement ... circulating tumor cells (CTCs) from cancer patients.  The ... in CTC levels correlate with clinical outcomes in ... These data will then be employed to support ...
(Date:6/24/2016)... ... 24, 2016 , ... While the majority of commercial spectrophotometers and fluorometers use ... 6000i models are higher end machines that use the more unconventional z-dimension of 20mm. ... from the bottom of the cuvette holder. , FireflySci has developed several Agilent ...
(Date:6/23/2016)... CAMBRIDGE, Mass. , June 23, 2016 /PRNewswire/ ... the development of novel compounds designed to target ... compound, napabucasin, has been granted Orphan Drug Designation ... in the treatment of gastric cancer, including gastroesophageal ... cancer stemness inhibitor designed to inhibit cancer stemness ...
Breaking Biology Technology: