Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


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


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:

More articles from Life Sciences:

nachricht First time-lapse footage of cell activity during limb regeneration
25.10.2016 | eLife

nachricht Phenotype at the push of a button
25.10.2016 | Institut für Pflanzenbiochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

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

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Greater Range and Longer Lifetime

26.10.2016 | Power and Electrical Engineering

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

More VideoLinks >>>