HOME >> BIOLOGY >> NEWS
Evidence of rapid evolution is found at the tips of chromosomes

In terms of their telomeres, mice are more complicated than humans. That's the finding from a recent Rockefeller University study, which shows that mice have two proteins working together to do the job of a single protein in human cells. The findings, published recently in Cell, suggest that the protein complex that protects chromosome ends may have evolved far more rapidly than previously believed.

Acting as caps on the ends of each chromosome, telomeres are composed of repetitive DNA and shelterin, a protective protein complex protects. Titia de Lange's lab has identified many of the components of shelterin and studies how its components work together to ensure that chromosome ends are not recognized as DNA breaks.

Previous work from the de Lange lab showed that TRF2, a shelterin protein that binds to the duplex part of the telomere, is crucial for telomere protection. Without TRF2, telomeres activate a DNA damage signal and are repaired by the same pathways that act on DNA breaks. TRF2 brings a second shelterin protein, POT1, to the telomeres. Because POT1 binds to single-stranded telomeric DNA present at the very end of the chromosomes, the de Lange lab asked how POT1 contributes to the protection of telomeres.

"We had previously removed TRF2 from mouse cells and seen many dramatic phenotypes," says de Lange, "all of the telomeres ligate together; there is a massive DNA damage response and the cells basically die. We argued that if the function of TRF2 was to bring POT1 to the DNA, then we should observe the same phenotype if we removed POT1."

To determine if this was the case, graduate student Dirk Hockemeyer, the first author of the paper, decided to remove the POT1 gene from mice. Humans have one POT1 gene, so de Lange and Hockemeyer were more than a bit surprised when they found two POT1 genes in the mouse genome. "Both genes are ubiquitously expressed and both are at telomeres," says de Lange. "Nothing prepared us
'"/>

Contact: Kristine Kelly
kkelly@rockefeller.edu
212-327-7146
Rockefeller University
1-Aug-2006


Page: 1 2

Related biology news :

1. A private bandwidth for communication in bats: Evidence from insular horseshoe bats
2. Evidence human activities have shaped large-scale ecological patterns
3. National Academies advisory: April 25 Symposium on Forensic Evidence
4. Evidence for expanded color vision for some colorblind individuals
5. Evidence of 600-million-year old fungi-algae symbiosis discovered in marine fossils
6. Evidence of waterfowl mediated gene-flow in aquatic invertebrates
7. Evidence that human brain evolution was a special event
8. Evidence that learning is consolidated during sleep
9. Indo-Pacific coral reefs disappearing more rapidly than expected
10. Gene expression patterns predict rapid decline in idiopathic pulmonary fibrosis patients
11. New way to catch cancers spread, rapid 3-D retinal imaging, more at CLEO/QELS 2007

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/4/2019)... ... June 04, 2019 , ... ... for salient features of seizure risk signals, usually based on variations of amplitude, ... remains the only acceptable diagnostic methodology due to the complexity and variability of ...
(Date:6/1/2019)... ... 2019 , ... The University of Vermont Health Network Ventures ... Series B Financing Round. , “With the commitment from the UVM fund ... and business resources to bear as we advance our biopharmaceutical products to the ...
(Date:5/31/2019)... (PRWEB) , ... May 30, 2019 , ... ... Comprehend in a live webinar on Wednesday, June 19, 2019 ... clinical operations teams, medical review teams, data management teams and contract research organizations ...
Breaking Biology News(10 mins):
(Date:6/11/2019)... , ... June 11, 2019 , ... ... Personalized Stem Cells Inc. (PSC) , has announced that their GMP facility ... Food and Drug Branch for manufacturing. This is an important milestone for ...
(Date:5/31/2019)... ... May 29, 2019 , ... For many years, the ... forms of cancer demand breakthrough therapies. Advances in immuno-oncology have led to the advent ... T cells with engineered T cell receptors known as “CARs”. The CAR enables the ...
(Date:5/31/2019)... ... May 30, 2019 , ... Object Pharma, Inc., ... strategic acquisition of Metabiologics, Inc., a globally recognized leader in the production and ... commercialization rights to a full spectrum of botulinum neurotoxins, as well as a ...
(Date:5/21/2019)... ... 21, 2019 , ... DuPont Nutrition & Biosciences (DuPont) and ... Brewing Conference dedicated to sharing brewing knowledge, strengthening relationships and discussing best practices ... through a partnership with “Ethiopia Invest”, will run through May 23, 2019, in ...
Breaking Biology Technology:
Cached News: