Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Suspect gene corrupts neural connections

18.08.2014

'Diseases of synapses' demo'd in a dish -- NIH-funded study

Researchers have long suspected that major mental disorders are genetically-rooted diseases of synapses – the connections between neurons. Now, investigators supported in part by the National Institutes of Health have demonstrated in patients' cells how a rare mutation in a suspect gene disrupts the turning on and off of dozens of other genes underlying these connections.


Synapses -- sites of intercellular communications -- are revealed in a mature iPSC cortex neuron derived from a participant in the study. Immune-based staining shows synapse markers (red, green) and the cell's nucleus (blue).

Credit: Hongjun Song, Ph.D., Johns Hopkins University

"Our results illustrate how genetic risk, abnormal brain development and synapse dysfunction can corrupt brain circuitry at the cellular level in complex psychiatric disorders," explained Hongjun Song, Ph.D. , of Johns Hopkins University, Baltimore, a grantee of the NIH's National Institute of Mental Health (NIMH), a funder of the study.

Song and colleagues, from universities in the United States, China, and Japan, report on their discovery in the journal Nature, August 18, 2014.

"The approach used in this study serves as a model for linking genetic clues to brain development," said NIMH director Thomas R. Insel, M.D.

Most major mental disorders, such as schizophrenia, are thought to be caused by a complex interplay of multiple genes and environmental factors. However, studying rare cases of a single disease-linked gene that runs in a family can provide shortcuts to discovery. Decades ago, researchers traced a high prevalence of schizophrenia and other major mental disorders – which often overlap genetically – in a Scottish clan to mutations in the gene DISC1 (Disrupted In Schizophrenia-1). But until now, most of what's known about cellular effects of such DISC1 mutations has come from studies in the rodent brain.

To learn how human neurons are affected, Song's team used a disease-in-a-dish technology called induced pluripotent stem cells (iPSCs). A patient's skin cells are first induced to revert to stem cells. Stem cells play a critical role in development of the organism by transforming into the entire range of specialized cells which make up an adult. In this experiment, these particular "reverted" stem cells were coaxed to differentiate into neurons, which could be studied developing and interacting in a petri dish. This makes it possible to pinpoint, for example, how a particular patient's mutation might impair synapses. Song and colleagues studied iPSCs from four members of an American family affected by DISC1-linked schizophrenia and genetically related mental disorders.

Strikingly, iPSC-induced neurons, of a type found in front brain areas implicated in psychosis, expressed 80 percent less of the protein made by the DISC1 gene in family members with the mutation, compared to members without the mutation. These mutant neurons showed deficient cellular machinery for communicating with other neurons at synapses.

The researchers traced these deficits to errant expression of genes known to be involved in synaptic transmission, brain development, and key extensions of neurons where synapses are located. Among these abnormally expressed genes were 89 previously linked to schizophrenia, bipolar disorder, depression, and other major mental disorders. This was surprising, as DISC1's role as a hub that regulates expression of many genes implicated in mental disorders had not previously been appreciated, say the researchers.

The clincher came when researchers experimentally produced the synapse deficits by genetically engineering the DISC1 mutation into otherwise normal iPSC neurons – and, conversely, corrected the synapse deficits in DISC1 mutant iPSC neurons by genetically engineering a fully functional DISC1 gene into them. This established that the DISC1 mutation, was, indeed the cause of the deficits.

The results suggest a common disease mechanism in major mental illnesses that integrates genetic risk, aberrant neurodevelopment, and synapse dysfunction. The overall approach may hold promise for testing potential treatments to correct synaptic deficits, say the researchers.

###

Reference:

Wen Z, Nguyen HN, Guo Z, Lalli MA, Wang X, Su Y, Kim N-S, Yoon K-J, Shin J, Zhang C, Makri G, Nauen D, Yu H, Guzman E, Chiang C-H, Yoritomo N, Kaibuchi K, Zou J, Christian KM, Cheng L, Ross CA, Margolis RL, Chen G, Kosik KS, Song H, Ming G-l. Synaptic dysregulation in a human iPS cell model of major mental disorders. Nature, Aug. 17, 2014.

About the National Institute of Mental Health (NIMH): The mission of the NIMH is to transform the understanding and treatment of mental illnesses through basic and clinical research, paving the way for prevention, recovery and cure. For more information, visit the NIMH website.

NINDS is the nation's leading funder of research on the brain and nervous system. The mission of NINDS is to seek fundamental knowledge about the brain and nervous system and to use that knowledge to reduce the burden of neurological disease.

About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.

Jules Asher | Eurek Alert!

Further reports about: DISC1 Health Mental NIH NIMH connections deficits diseases disorders genes genetically neurons schizophrenia synapses

More articles from Life Sciences:

nachricht Cells migrate collectively by intermittent bursts of activity
30.09.2016 | Aalto University

nachricht The structure of the BinAB toxin revealed: one small step for Man, a major problem for mosquitoes!
30.09.2016 | CNRS (Délégation Paris Michel-Ange)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First-Ever 3D Printed Excavator Project Advances Large-Scale Additive Manufacturing R&D

Heavy construction machinery is the focus of Oak Ridge National Laboratory’s latest advance in additive manufacturing research. With industry partners and university students, ORNL researchers are designing and producing the world’s first 3D printed excavator, a prototype that will leverage large-scale AM technologies and explore the feasibility of printing with metal alloys.

Increasing the size and speed of metal-based 3D printing techniques, using low-cost alloys like steel and aluminum, could create new industrial applications...

Im Focus: New welding process joins dissimilar sheets better

Friction stir welding is a still-young and thus often unfamiliar pressure welding process for joining flat components and semi-finished components made of light metals.
Scientists at the University of Stuttgart have now developed two new process variants that will considerably expand the areas of application for friction stir welding.
Technologie-Lizenz-Büro (TLB) GmbH supports the University of Stuttgart in patenting and marketing its innovations.

Friction stir welding is a still-young and thus often unfamiliar pressure welding process for joining flat components and semi-finished components made of...

Im Focus: First quantum photonic circuit with electrically driven light source

Optical quantum computers can revolutionize computer technology. A team of researchers led by scientists from Münster University and KIT now succeeded in putting a quantum optical experimental set-up onto a chip. In doing so, they have met one of the requirements for making it possible to use photonic circuits for optical quantum computers.

Optical quantum computers are what people are pinning their hopes on for tomorrow’s computer technology – whether for tap-proof data encryption, ultrafast...

Im Focus: OLED microdisplays in data glasses for improved human-machine interaction

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.

“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...

Im Focus: Artificial Intelligence Helps in the Discovery of New Materials

With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.

Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Paper – Panacea Green Infrastructure?

30.09.2016 | Event News

HLF: From an experiment to an establishment

29.09.2016 | Event News

European Health Forum Gastein 2016 kicks off today

28.09.2016 | Event News

 
Latest News

First-Ever 3D Printed Excavator Project Advances Large-Scale Additive Manufacturing R&D

30.09.2016 | Materials Sciences

New Technique for Finding Weakness in Earth’s Crust

30.09.2016 | Earth Sciences

Cells migrate collectively by intermittent bursts of activity

30.09.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>