Navigation Links
CSHL researchers explain process by which cells 'hide' potentially dangerous DNA segments
Date:4/9/2009

which the velcro-like protein Chp1 binds to methylated chromatin.

"We found that a part of Chp1 known as the chromodomain binds with high affinity (or strength) to methylated chromatin," explains Thomas Schalch, Ph.D., a postdoctoral researcher in the Joshua-Tor lab who led the current study. By teasing apart the origin of this unique affinity, the CSHL team stumbled across Chp1 mutants that would produce siRNAs but could not assemble heterochromatin.

"These results lead us to think that the tight interaction between RITS and the methyl marks is a requirement at least as important as the availability of siRNA," Schalch says.

A crystal structure provides the answer

The team wanted to know the exact points of contact between Chp1 and its target and how these interactions contributed to the strength of binding. For these answers, Schalch and the CSHL team made use of Joshua-Tor's expertise in X-ray crystallography the science of determining the exact position of atoms and bonds within a molecule by creating a crystal, which is then probed with powerful x-rays.

Disrupting each point of interaction between Chp1 and its target by engineering various mutations into the Chp1 protein decreased the strength of binding to different levels. Even a five-fold decrease in binding strength prevented the mutation-bearing cells from assembling new heterochromatin, even though some of the mutants were able to generate siRNAs.

This work reveals that siRNAs cannot by themselves establish heterochromatin when Chp1's binding to H3K9me the methylated chromatin is impaired. Whether this mechanism of heterochromatin assembly discovered in yeast also occurs in mammalian cells is unclear at this point, according to Schalch, as a mammalian equivalent to Chp1 has not been found. "But we've now identified a fingerprint for the high-affinity interaction between a chromatin-binding protein and its 'marked', or methylated, target," says Sch
'/>"/>

Contact: Hema Bashyam
bashyam@cshl.edu
516-367-6822
Cold Spring Harbor Laboratory
Source:Eurekalert

Page: 1 2 3 4

Related biology news :

1. Stem cell therapy makes cloudy corneas clear, according to Pitt researchers
2. Biomedical researchers invited to design experiments for the International Space Station
3. Caltech researchers train computers to analyze fruit-fly behavior
4. International climate change researchers meet, review latest findings
5. Einstein researchers devise a fast and sensitive way to detect ricin
6. NC State researchers find soy may aid in treating canine cancers
7. Queens researchers shine light on compact fluorescent bulb problems
8. Penn researchers demonstrate a new model for drug discovery with a fluorescent anesthetic
9. Researchers discover primer to plant defense system
10. MDC researchers prevent virus induced myocarditis
11. Researchers examine bacterial rice diseases, search for genetic solutions
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:7/24/2014)... native animal species for food or commercial food sale, ... in the decline of many species of primates and ... more than half of the species being consumed are ... surveying not only the meat made available for sale ... forest by hunters and brought to villages for consumption, ...
(Date:7/24/2014)... has different effects on different species of fish, ... of Bristol and Exeter which tested fish anti-predator ... a flying seagull predator model when exposed to ... European minnows. , Lead author Dr Irene ... "Noise levels in many aquatic environments have increased ...
(Date:7/24/2014)... a smog-free Los Angeles, where electric cars ply silent ... on heat from beneath the earth, from howling winds ... Stanford study finds that it is technically and economically ... powered by clean, renewable energy. Published in Energy ... inexpensive and reliable energy supply in California that could ...
Breaking Biology News(10 mins):Stanford study shows how to power California with wind, water and sun 2Stanford study shows how to power California with wind, water and sun 3Stanford study shows how to power California with wind, water and sun 4
... UT Southwestern Medical Center scientists have synthesized a peptide ... treating infections, neurodegenerative disorders, and cancer through an ability ... is a fundamental recycling process in which intracellular enzymes ... their individual building blocks, which are then reassembled into ...
... generation destroy malignant breast tumors in a targeted manner: ... receptors for the hormones estrogen or progesterone, or a ... But about one in every six breast tumors has ... particularly aggressive and notoriously difficult to treat. ...
... rising a threat to island nations. As a group ... found out, at the same time, tiny single-cell organisms are ... able to mitigate the consequences of climate change. ... and reefs with their calcareous shells. The study,s results have ...
Cached Biology News:Unique peptide could treat cancers, neurological disorders, and infectious diseases 22 antibodies are better than 1 2Profiting from climate change 2Profiting from climate change 3
(Date:7/25/2014)... DUBLIN , July 25, 2014 ... of the "Global Metabolomics Market 2014-2018" ... http://photos.prnewswire.com/prnh/20130307/600769 Metabolomics or Metabonomics ... metabolites. Metabolomics has become a new experimental technique ... and the environmental sciences. Metabolites are small molecules ...
(Date:7/25/2014)... July 25, 2014 WABC Radio show out ... with Lorry Young will be hosting California-based Vet-Stem, Inc.’s ... stem cell therapy in pets. Dr. Harman first visited ... stem cell therapy for pets suffering from osteoarthritis and other ... Veterinary Medicine industry forward. , Young has invited Dr. Harman ...
(Date:7/25/2014)... July 25, 2014 Lawrence Livermore scientists ... Thomson Reuters list of " The World's Most Influential ... of the 3,000 researchers who were identified by analyzing ... those who published the highest-impact work (2002-2012 and 2012-2013). ... on combustion modeling . , "This recognition is ...
(Date:7/25/2014)... 2014 /PRNewswire-iReach/ -- Xybion Corporation, the leading provider ... operating in highly regulated industries, announced today that ... User Group Conference, Xybion International Exchange, on October ... at the Sheraton Society Hill Hotel.  ... This year,s conference theme is Compliance ...
Breaking Biology Technology:Global Metabolomics Market 2014-2018: Key Vendors are Agilent, Bio-Rad, Bruker, Human Metabolome and Metabolon 2Robert J. Harman, DVM, Founder and CEO of Vet-Stem, Inc. to Join New York Radio Host Lorry Young in Upcoming Episode of A “Paws” For Your Pet 2Robert J. Harman, DVM, Founder and CEO of Vet-Stem, Inc. to Join New York Radio Host Lorry Young in Upcoming Episode of A “Paws” For Your Pet 3Scientists Burst onto Influential List for Combustion Research 2Scientists Burst onto Influential List for Combustion Research 3Scientists Burst onto Influential List for Combustion Research 4Xybion Announces It Will Host International User Conference in Philadelphia 2Xybion Announces It Will Host International User Conference in Philadelphia 3
... PHILADELPHIA, Aug. 23, 2011 FMC Corporation (NYSE: ... has entered into two exclusive agreements covering global development ... and ornamental markets.  FMC will begin commercialization this year ... start development for new biological standalone and combination products ...
... Additional   Funds to   Broaden   ... , AU$6.25M (US$6.5M) investment by GBS Venture Partners, ... additional Phase 2 studies will run in parallel with planned clinical ... an Australian pain drug development company, today announced it has ...
... not easy, especially for tiny nanowires: With no ... difficult to harness their full potential as effective ... Chemistry Faculty has found a way to grow ... providing, for the first time, the much-needed guidance ...
Cached Biology Technology:FMC Corporation Announces Exclusive Global Development and Supply Agreements for Chr. Hansen Biological Products 2Spinifex Closes AU$18.25M(~US$19M) Expanded Series B Round 2Spinifex Closes AU$18.25M(~US$19M) Expanded Series B Round 3Spinifex Closes AU$18.25M(~US$19M) Expanded Series B Round 4Spinifex Closes AU$18.25M(~US$19M) Expanded Series B Round 5Nanowires get into the groove 2
...
... scattering detector for ambient HPLC. Contains ... hardware for two external devices such ... contains an analog output from the ... chart recorders. Includes an input for ...
... an imaging based plate reader for ... throughput screening which can utilize both ... light sources and cameras in the ... in photon detection technology. It ...
... StdSens reagents and supplies, for 10 ... sufficient to perform standard-sensitivity RNA analysis ... the Experion automated electrophoresis system. Supplied ... microliters RNA StdSens stain, 20 microliters ...
Biology Products: