Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Newly discovered mechanism can explain the Beckwith-Wiedemann syndrome

27.10.2008
Researchers from Uppsala University have discovered a mechanism that silences several genes in a chromosome domain. The findings, published in today’s on-line issue of Molecular Cell, have implications in understanding the human disorder Beckwith-Wiedemann syndrome.

In mammals the cells contain two copies of each chromosome, one inherited from the mother and one from the father. The genes on the chromosomes can either be active or inactive. If a gene is active on the maternal chromosome, the corresponding gene is usually active also on paternal chromosome.

However, in some domains of the chromosome the activity is shut down on one of the chromosomes but not on the other. The genes in these domains cannot be activated the normal way but are completely silenced. The present study shows for the first time how this silencing of several genes on a chromosome is accomplished.

The research group, led by Chandrasekhar Kanduri, has studied a domain with several silenced genes on chromosome 7 in the mouse. The corresponding domain with silenced genes is located on the human chromosome 11. When part of this domain is transcribed a long RNA molecule, Kcnq1ot1-RNA, is formed. This RNA does not give rise to any protein, instead it mediates the silencing of eight to ten genes in a much larger area on the chromosome.

Based on their findings the researchers have suggested a model for how this is accomplished. The Kcnq1ot1-RNA binds to the DNA in the domain and recruits specific enzymes that chemically modify DNA-binding proteins. This modification makes the DNA inaccessible for transcription and thereby the genes cannot be activated. In addition, the Kcnq1ot1-RNA targets the silenced domain to a specific area in the cell nucleus. There it is protected during cell division and the genes will stay silenced also in the daughter cells.

– We show for the first time how a long RNA molecule can establish and maintain silencing of multiple genes in a large domain on the chromosome, says Chandrasekhar Kanduri. The popular belief is that it is only a gene located in the same area as where the long RNA molecule is transcribed from that can be silenced.

This mechanism is important for understanding the genetic disorder Beckwith-Wiedemann Syndrome. In this condition silencing of the chromosome 11 domain does not function properly and both copies of the genes in the domain become inactive, instead of just one. Less protein is produced from the genes, leading to the excess growth characteristics associated with the syndrome: enlargement of organs in the foetus and an increased risk for tumours in the affected organs.

Anneli Waara | alfa
Further information:
http://www.uu.se

More articles from Life Sciences:

nachricht Closing the carbon loop
08.12.2016 | University of Pittsburgh

nachricht Newly discovered bacteria-binding protein in the intestine
08.12.2016 | University of Gothenburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Closing the carbon loop

08.12.2016 | Life Sciences

Applicability of dynamic facilitation theory to binary hard disk systems

08.12.2016 | Physics and Astronomy

Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D

08.12.2016 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>