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:
(Date:4/16/2014)... memories improves during childhood, associated with structural changes ... and parietal cortices. New research from UC Davis ... this crucial time. Eventually, that could give insights ... into and during adolescence and affect memory, such ... the middle of the brain, the hippocampus plays ...
(Date:4/16/2014)... composed of Dr. Martin Prechtl, Leo Heim and their ... has discovered a new method of generating hydrogen using ... is of particular interest when it comes to fuel ... and mild hydrogen production using water and formaldehyde", have ... . , Among other applications, the new approach can ...
(Date:4/15/2014)... away in Hartford, Connecticut, a Puerto Rican community is ... that is so authentic it has caught the attention ... Gregory J. Anderson (University of Connecticut) took a close ... markets of Hartford and uncovered evidence that gives new ... using for years: home is in the kitchen. , ...
Breaking Biology News(10 mins):How kids' brain structures grow as memory develops 2The human food connection: A new study reveals more about our relationship to food 2The human food connection: A new study reveals more about our relationship to food 3
(Date:1/15/2014)... device," Nobel laureate Herbert Kroemer famously observed, ... found at the junctures where layers of ... of nanotechnology, the interfaces between layers of ... applications in such high-tech favorites as spintronics, ... vast potential of these metal oxide interfaces, ...
(Date:1/15/2014)... Jan. 15, 2014   Niagara Thermal Products ... been selected by Buffalo BioBlower Technologies LLC ("B3") ... of its SBIR Phase 2 award from the ... only comprehensive air purification system that kills all ... pollutants, allergens and organic particulates.  In independent testing ...
(Date:1/15/2014)... SAN JOSE, California , January 15, 2014 ... company developing antibody-drug conjugates for cancer, today announced the ... Board of Directors. Dr Reynolds has over 20 years, ... as Chief Medical Officer at Seattle Genetics. ... time for Oxford BioTherapeutics, as the company completes its ...
(Date:1/15/2014)... -- A study has been launched to ... Formula 1 track could help to tackle the problem ... Technologies (MAT), Stowhealth (a GP surgery based in Stowmarket) ... by healthcare provider Simplyhealth. Telemetry technology, which ... the on-track performance of Vodafone McLaren Mercedes Formula 1 ...
Breaking Biology Technology:A deeper look at interfaces 2Niagara Thermal Products LLC Selected as Critical Supplier for Buffalo BioBlower Air Purification Systems 2Oxford BioTherapeutics Appoints Thomas C Reynolds MD, PhD to its Board of Directors 2Oxford BioTherapeutics Appoints Thomas C Reynolds MD, PhD to its Board of Directors 3Formula 1 Technology Tackles Obesity in Unique Healthcare Partnership 2Formula 1 Technology Tackles Obesity in Unique Healthcare Partnership 3Formula 1 Technology Tackles Obesity in Unique Healthcare Partnership 4
Cached News: