Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New insight into fragile X syndrome: Scientists identify possible link to RNAi

01.10.2002


Two independent research groups, led by Drs. Haruhiko Siomi (Institute for Genome Research, University of Tokushima, Japan) and Gregory Hannon (Cold Spring Harbor Laboratory, USA) have discovered that the Drosophila version of the human fragile X mental retardation protein associates with components of the RNAi pathway, suggesting that the molecular mechanism underlying fragile X syndrome may involve an RNAi-related process.



"It has been our feeling since we became involved in the field several years ago that only through an understanding of the mechanism of RNAi would we be able to understand the biological implications of this process," states Dr. Hannon.

Fragile X syndrome is the most common form of hereditary mental retardation, affecting 1 in 4000 males and 1 in 8000 females. Fragile X syndrome is the result of a genetic mutation at one end of the fragile X mental retardation 1 gene (FMR1) that causes the abnormal inactivation of the gene. It is known that the protein encoded by FMR1 -- the so-called fragile X mental retardation protein (FMRP) -- binds to RNA and is thought to regulate the expression of specific genes during neural development, but the mode of FMRP action in cells is yet to be defined.


This work provides some important clues.

Using Drosophila as a model organism, Drs. Siomi and Hannon and colleagues found that FMRP associates with RNAi-related cellular machinery. RNAi-induced gene silencing depends upon the introduction of double-stranded RNA, which is processed by Dicer enzymes into short pieces of double-stranded RNA. These short interfering RNAs, or siRNAs as they are known, are incorporated into an RNAi-induced silencing complex (RISC), which uses them as a guide to target and destroy complementary mRNAs, and thereby prevent synthesis of the encoded protein.

Both teams of researchers identified an association between FMRP, short double-stranded RNAs, and a previously identified subunit of RISC (a protein called AGO2); Dr. Siomi and colleagues also found that FMRP associates with the Dicer processing enzyme. These finding suggest that FMRP may function in an RNAi-related process to regulate the expression of its target genes at the level of translation (protein synthesis).

Further delineation of both the identity of FMRP target genes and how changes in their expression patterns can alter the neural landscape in such a way as to result in mental retardation are needed, but as Dr. Siomi explains, "the link between the fragile X syndrome as a phenotype and a possible role for defects in an RNAi-related apparatus through loss of the FMR1 protein will likely open up an entirely new field of molecular human genetics: defects in an RNAi-related apparatus that cause disease."

Heather Cosel | EurekAlert!
Further information:
http://www.cshl.org/

More articles from Life Sciences:

nachricht Decoding the genome's cryptic language
27.02.2017 | University of California - San Diego

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

New pop-up strategy inspired by cuts, not folds

27.02.2017 | Materials Sciences

Sandia uses confined nanoparticles to improve hydrogen storage materials performance

27.02.2017 | Interdisciplinary Research

Decoding the genome's cryptic language

27.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>