Trio of autism-linked molecules orchestrate neuron connections


The findings, published in the Jan. 14 issue of the journal Cell, may also lend insight into brain disorders including autism, depression and addiction, because previous research has linked these proteins individually to those diseases.

“We may have pinpointed a developmental process that may be critically impaired in diseases such as autism, and that’s really exciting,” said Cagla Eroglu, an assistant professor of cell biology and neurobiology at the Duke University School of Medicine, who led the research.

The new work focused on the neurons that pass information from the brain’s thalamus — which processes sensory information — to the cortex, which is important for memory, attention and consciousness, among other roles. In late 2014, Eroglu’s group found that a protein called ‘hevin’, produced by crucial non-neuronal brain cells called astrocytes, helps new neuronal connections form from the thalamus to the cortex in mice, but exactly how was unclear.

The group thought that two other types of proteins, neurexins and neuroligins, might be involved. Neurexins are present on the message-sending sides of neurons, whereas neuroligins are on the receiving ends. These proteins are thought to align new neuronal contacts so that they can pass signals within the small gaps between them, called synapses.

“There is an interesting code between neurexins and neuroligins that determines whether they form contacts between each other,” said Eroglu, who is also a member of the Duke Institute for Brain Sciences. “Some forms of these molecules seem to prefer each other and make contacts, while some don’t interact with each other at all. What we found here, which was surprising, is that astrocytes secrete hevin to alter this code.”

Read More: Sciencedaily