Navigation Links
Tiny RNA molecules fine-tune the brain's synapses

Non-coding regions of the genome ?those that don't code for proteins ?are now known to include important elements that regulate gene activity. Among those elements are microRNAs, tiny, recently discovered RNA molecules that suppress gene expression.

Increasing evidence indicates a role for microRNAs in the developing nervous system, and researchers from Children's Hospital Boston now demonstrate that one microRNA affects the development of synapses ?the points of communication between brain cells that underlie learning and memory. The findings appear in the January 19th issue of Nature.

"This paper provides the first evidence that microRNAs have a role at the synapse, allowing for a new level of regulation of gene expression," says senior author Michael Greenberg, PhD, Director of Neuroscience at Children's Hospital Boston. "What we've found is a new mechanism for regulating brain function."

The brain's ability to form and refine synapses allows organisms to learn and respond to their environment, strengthening important synaptic connections, forming new ones, and allowing unimportant ones to weaken. Experiments in Greenberg's lab, done in rats, showed that a microRNA called miR-134 regulates the size of dendritic spines, the protrusions from a neuron's dendrites where synapses form. When neurons were exposed to miR-134, spine volume significantly decreased, weakening the synapse. When miR-134 was inhibited, spines increased in size, strengthening the synapse.

Further experiments showed that miR-134 acts by inhibiting expression of a gene called Limk1, which causes dendritic spines to grow. When neurons were exposed to a growth factor known as brain-derived neurotrophic factor (BDNF), this inhibition was overcome and Limk1 became active again, enhancing spine growth.

Greenberg believes that miR-134 ?and other microRNAs his lab is studying ?may play a role in fine-tuning cognitive function by selectively controlling synapse de velopment in response to environmental stimuli. "A single neuron can form a thousand synapses," says Greenberg, also a professor of neurology and neuroscience at Harvard Medical School. "If you could selectively control what's happening at one synapse without affecting another, you greatly increase the information storage and computational capacity of the brain."

Greenberg also speculates that miR-134 may be relevant to disorders such as mental retardation and autism. He notes that loss of Limk1 due to a chromosomal deletion is associated with Williams syndrome, and that the BDNF pathway that activates Limk1 includes proteins that are disabled in tuberous sclerosis and Fragile X syndrome. All three genetic disorders can cause cognitive impairment and autistic-like behaviors.


'"/>

Source:Children's Hospital Boston


Related biology news :

1. Inflammatory molecules released by pollen trigger allergies
2. Medical molecules designed to respond to visible light that can penetrate tissue
3. DNA constraints control structure of attached macromolecules
4. Scientists discover that three molecules may be developed into new Alzheimers drugs
5. Physical and functional interaction of key cell growth molecules linked to cancer
6. Scientists discover new way to look at how molecules twist and turn on water
7. Scientists learn to predict protein-stabilizing ability of small molecules
8. Convergent evolution of molecules in electric fish
9. Micro-boxes of water used to study single molecules
10. Researchers unveil strategy for creating actively-programmed anti-cancer molecules
11. Biological motors sort molecules one by one on a chip
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/28/2016)... 2016 First quarter 2016:   ... with the first quarter of 2015 The gross margin ... (loss: 18.8) and the operating margin was 40% (-13) ... Cash flow from operations was SEK 249.9 M (21.2) , ... unchanged, SEK 7,000-8,500 M. The operating margin for 2016 ...
(Date:4/19/2016)... -- The new GEZE SecuLogic access control ... system solution for all door components. It can be ... interface with integration authorization management system, and thus fulfills ... dimensions of the access control and the optimum integration ... considerable freedom of design with regard to the doors. ...
(Date:4/14/2016)... , April 14, 2016 ... and Malware Detection, today announced the appointment of ... the new role. Goldwerger,s leadership appointment comes ... the heels of the deployment of its platform at ... behavioral biometric technology, which discerns unique cognitive and physiological ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... On Wednesday, June 22, 2016, the ... the Dow Jones Industrial Average edged 0.27% lower to finish ... 0.17%. Stock-Callers.com has initiated coverage on the following equities: Infinity ... NKTR ), Aralez Pharmaceuticals Inc. (NASDAQ: ... ). Learn more about these stocks by accessing their free ...
(Date:6/23/2016)... ... June 23, 2016 , ... Regulatory Compliance Associates® Inc. ... a free webinar on Performing Quality Investigations: Getting to Root Cause. ... at no charge. , Incomplete investigations are still a major concern to the ...
(Date:6/23/2016)... 2016  Amgen (NASDAQ: AMGN ) today ... life sciences incubator to accelerate the development of ... space at QB3@953 was created to help high-potential life ... many early stage organizations - access to laboratory infrastructure. ... launched two "Amgen Golden Ticket" awards, providing each winner ...
(Date:6/22/2016)... 22, 2016 Cell Applications, Inc. and ... to produce up to one billion human induced ... one week. These high-quality, consistent stem cells enable ... and spend more time doing meaningful, relevant research. ... high-volume manufacturing process that produces affordable, reliable HiPSC ...
Breaking Biology Technology: