Synaptic Transmission

Background: Cholinergic neuronal loss is one of the hallmarks of AD related neurodegeneration; however, preclinical promise of α7 nAChR drugs failed to translate into humans. CHRFAM7A, a uniquely human fusion gene, is a negative regulator of α7 nAChR and was unaccounted for in preclinical models. Methods: Molecular methods: Function of CHRFAM7A alleles was studied in vitro in two disease relevant phenotypic readouts: electrophysiology and Aβ uptake. Genome edited human induced pluripotent stem cells (iPSC) were used as a model system with the human context.
Here, Nestler and Lüscher link addiction circuits to epigenetic mechanisms that are engaged by drug exposure or reflect life experience. These molecular alterations may not only explain the basis of drug-evoked synaptic plasticity, but may also help understand individual addiction vulnerability.
Altered synaptic structure and function is a major hallmark of fragile X syndrome (FXS), autism spectrum disorders (ASDs), and other intellectual disabilities (IDs), which are therefore classified as synaptopathies. FXS and ASDs, while clinically and genetically distinct, share significant comorbidity, suggesting that there may be a common molecular and/or cellular basis, presumably at the synapse.
Recent progress in the genomics of non-syndromic autism spectrum disorder (nsASD) highlights rare, large-effect, germline, heterozygous de novo coding mutations. This distinguishes nsASD from later-onset psychiatric disorders where gene discovery efforts have predominantly yielded common alleles of small effect. These differences point to distinctive opportunities for clarifying the neurobiology of nsASD and developing novel treatments.