Autism is considered among the most devastating neurological disorder conditions of early childhood. Now, researchers working in part at SSRL's Beam Line 4-2 have determined a three-dimensional structural model of a complex with the only two extracellular synaptic proteins implicated in autism spectrum disorders and mental retardation. Such a finding could deepen our understanding of this mysterious and debilitating type of disorder. The findings were published in the June 2007 edition of the journal Structure.

Many neurodevelopmental disorders involve abnormal synaptic function. Synapses provide essential connections between nerve cells in the brain that enable signals to be transmitted. Neurexin and neuroligins are proteins that associate in the extracellular space between synapses in the brain, and they appear to play a crucial role in maintaining the functionality of the brain's synaptic circuitry.

The research team combined small angle x-ray scattering data collected at SSRL with neutron solution scattering data to determine the molecular shapes of neuroligin and neurexin, which led to the creation of a model of the neurexin and neuroligin complex in the synaptic space. This new model provides an important structural framework for linking genetic information on mutated neurexins and neuroligins with neuro-developmental disorders.

To learn more about this research see the full scientific highlight at:
http://www-ssrl.slac.stanford.edu/research/highlights_archive/neuroligin_autism.html

Comoletti D, Grishaev A, Whitten AE, Tsigelny I, Taylor P, Trewhella J. (2007) Synaptic arrangement of the neuroligin/beta-neurexin complex revealed by X-ray and neutron scattering. Structure. 15:693-705.