HOME >> BIOLOGY >> NEWS
Revealed: How a master protein remodels chromosomes to orchestrate gene expression

A team led by Terumi Kohwi-Shigematsu of Lawrence Berkeley National Laboratory's Life Sciences Division has demonstrated that SATB1, a protein crucial to the development of the immune system, works by forming a network in the cell nucleus, attaching chromatin to the network structure at specific sites, and orchestrating remodeling of the chromatin over long distances to regulate gene expression.

"SATB1 determines when and how the genes are read -- when they are activated and when they are repressed," says Kohwi-Shigematsu. "We have shown that SATB1 regulates gene transcription by functioning as a 'landing platform' for several chromatin remodeling enzymes, which operate within large but well defined domains."

In the 10 October 2002 issue of Nature, the researchers report that, in thymocytes, SATB1 regulates the interleukin-2 receptor-alpha gene, IL?2Ra, by bringing specific chromatin and nucleosome remodeling enzymes directly to the gene site, and by directing nucleosome positioning over 7,000 base-pairs away.

Chromatin is the complex of DNA and proteins in the nucleus of the cell. It consists of DNA wound like thread around groups of histone proteins to form bead-like nucleosomes; this string of nucleosomes is coiled into fibers 30 nanometers (billionths of a meter) thick, and the fibers are folded into chromatin loops, further compacting the DNA. Thus a eukaryotic cell can pack the entire genome of the organism, well over a meter of DNA, into a nucleus only a few millionths of a meter across.

Many orders of chromatin folding are necessary to fit the genome into a small nucleus, and this complicates the process of gene expression. For a gene to be transcribed, the double-stranded DNA that encodes it has to be unzipped -- hard to do inside tightly wound chromatin. So gene expression depends on molecular machines that rearrange the chromatin, repositioning nucleosomes along the DNA fibers.

A decade ago Kohwi-Shigematsu a
'"/>

Contact: Paul Preuss
paul_preuss@lbl.gov
510-486-6249
DOE/Lawrence Berkeley National Laboratory
9-Oct-2002


Page: 1 2 3 4

Related biology news :

1. Newly identified master gene key in babys first breath
2. Genetic master switch sends bacteria toward seafood dinner
3. Brains master molecule produces same behavior in mice from three different psychostimulant drugs
4. New approach to gene knockouts reveals the master planners of the skeleton
5. Scientists identify master molecule that controls action of many genes
6. Another job discovered for a master metabolic off-switch
7. Protein discovery tied to DNA master switch
8. School kids as master gardeners
9. DNA arrays decipher genomes master switches
10. New discovery: footprint shows master switch simultaneously controls plants disease defenses
11. New molecular link key to cellular proteins involved in cancer progression, other diseases

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


(Date:4/11/2017)... Florida , April 11, 2017 ... a security technology company, announces the appointment of independent Directors ... Bendheim to its Board of Directors, furthering the company,s ... ... of NXT-ID, we look forward to their guidance and benefiting ...
(Date:4/4/2017)... --  EyeLock LLC , a leader of iris-based identity ... and Trademark Office (USPTO) has issued U.S. Patent No. ... iris image with a face image acquired in sequence ... th issued patent. "The issuance ... multi-modal biometric capabilities that have recently come to market ...
(Date:3/29/2017)... , March 29, 2017  higi, the health IT ... North America , today announced a ... the acquisition of EveryMove. The new investment and acquisition ... of tools to transform population health activities through the ... data. higi collects and secures data today ...
Breaking Biology News(10 mins):
(Date:10/10/2017)... SANTA BARBARA, CALIFORNIA (PRWEB) , ... October 10, ... ... risk management, technological innovation and business process optimization firm for the life sciences ... the BoxWorks conference in San Francisco. , The presentation, “Automating GxP ...
(Date:10/9/2017)... ... 2017 , ... At its national board meeting in North Carolina, ARCS® ... Departments of Physics and Astronomy, has been selected for membership in ARCS Alumni ... the 2015 Breakthrough Prize in Fundamental physics for the discovery of the accelerating expansion ...
(Date:10/7/2017)... (PRWEB) , ... October 06, ... ... leader in Hi-C-based genomic technologies, launched its ProxiMeta™ Hi-C metagenome deconvolution product, ... Hi-C kit and accompanying cloud-based bioinformatics software to perform Hi-C metagenome deconvolution ...
(Date:10/5/2017)... ... October 05, 2017 , ... LabRoots , the leading provider ... the world, is giving back to cancer research with a month-long promotion supporting the ... through October 31, shoppers can use promo code PinkRibbon to get 10 percent off ...
Breaking Biology Technology:
Cached News: