Scientists find mechanism that constructs key brain structure

Sep 16, 2009
Neurons in green are over expressing a key gene that abnormally segregates them from other neurons (red and blue) within a developing column in the cerebral cortex. Credit: Yale University

Yale University researchers have found a molecular mechanism that allows the proper mixing of neurons during the formation of columns essential for the operation of the cerebral cortex, they report in the Sept. 16 online issue of the journal Nature.

Scientists have known for years that information processing in the cerebral cortex depends upon groupings of that assemble in the shape of vertical columns. If the number and mix of neurons in the column are wrong, severe can result. For instance, malformations of these columns have been implicated in some forms of autism and mental retardation. Scientists, however, have not been able to find the responsible for this intermixing.

In the Nature paper, a team led by Pasko Rakic, professor and chairman of the Department of Neurobiology and head of the Kavli Institute for Neuroscience, describes one of the molecular mechanisms essential to the organizations of these key structures.

Using the most advanced molecular technology, the Yale team showed that during neuronal migration, the intermixing of neurons within column depends on the expression levels of two genes - A-type Eph receptor and ephrin-As, a ligand, or molecule that binds to the receptor. failed to move laterally into proper columns in mice lacking the ligands or receptors, the team reported.

Masaaki Torii, the first author of the paper, said he was surprised to find that the tiny lateral shift of migrating neurons controlled by these molecules plays such a pivotal role in the normal cortical development.

"This so far unrecognized mechanism for lateral neuronal dispersion seems to be essential for the proper intermixing of neuronal types in the cortical columns, which, when disrupted, might contribute to neuropsychiatric disorders " said Rakic.

Source: Yale University (news : web)

Explore further: New mapping approach lets scientists zoom in and out as the brain processes sound

add to favorites email to friend print save as pdf

Related Stories

A molecule that protects from neuronal disorders

Sep 15, 2007

Many neuronal disorders, including epilepsy, schizophrenia and lissencephaly – a form of mental retardation -, result from abnormal migration of nerve cells during the development of the brain. Researchers from the Mouse ...

The beginnings of the thinking brain

Jun 28, 2006

Oxford researchers have identified the very first neurons in the human cerebral cortex, the part of the brain that sets us apart from all other animals.

The fancier the cortex, the smarter the brain?

Jul 17, 2009

Why are some people smarter than others? In a new article in Current Directions in Psychological Science, a journal of the Association for Psychological Science, Eduardo Mercado III from the University at Buffalo, The St ...

Recommended for you

Birthday matters for wiring-up the brain's vision centers

16 hours ago

Researchers at the University of California, San Diego School of Medicine have evidence suggesting that neurons in the developing brains of mice are guided by a simple but elegant birth order rule that allows them to find ...

How is depression related to dementia?

Jul 30, 2014

A new study by neuropsychiatric researchers at Rush University Medical Center gives insight into the relationship between depression and dementia. The study is published in the July 30, 2014, online issue of Neurology, the me ...

User comments : 0