Non-canonical function of ADAM10 in presynaptic plasticity.

A Disintegrin And Metalloproteinase 10 (ADAM10) plays a pivotal role in shaping neuronal networks by orchestrating the activity of numerous membrane proteins through the shedding of their extracellular domains. Despite its significance in the brain, the specific cellular localization of ADAM10 remains not well understood due to a lack of appropriate tools. Here, using a specific ADAM10 antibody suitable for immunostainings, we observed that ADAM10 is localized to presynapses and especially enriched at presynaptic vesicles of mossy fiber (MF)-CA3 synapses in the hippocampus.

Rescue of deficits by Brwd1 copy number restoration in the Ts65Dn mouse model of Down syndrome.

With an incidence of ~1 in 800 births, Down syndrome (DS) is the most common chromosomal condition linked to intellectual disability worldwide. While the genetic basis of DS has been identified as a triplication of chromosome 21 (HSA21), the genes encoded from HSA21 that directly contribute to cognitive deficits remain incompletely understood. Here, we found that the HSA21-encoded chromatin effector, BRWD1, was upregulated in neurons derived from iPS cells from an individual with Down syndrome and brain of trisomic mice.

Multiscale causal networks identify VGF as a key regulator of Alzheimer's disease.

Though discovered over 100 years ago, the molecular foundation of sporadic Alzheimer's disease (AD) remains elusive. To better characterize the complex nature of AD, we constructed multiscale causal networks on a large human AD multi-omics dataset, integrating clinical features of AD, DNA variation, and gene- and protein-expression. These probabilistic causal models enabled detection, prioritization and replication of high-confidence master regulators of AD-associated networks, including the top predicted regulator, VGF.

miR155 regulation of behavior, neuropathology, and cortical transcriptomics in Alzheimer's disease.

MicroRNAs are recognized as important regulators of many facets of physiological brain function while also being implicated in the pathogenesis of several neurological disorders. Dysregulation of miR155 is widely reported across a variety of neurodegenerative conditions, including Alzheimer's disease (AD), Parkinson's disease, amyotrophic lateral sclerosis, and traumatic brain injury. In previous work, we observed that experimentally validated miR155 gene targets were consistently enriched among genes identified as differentially expressed across multiple brain tissue and disease contexts.

Cytoskeletal makeup of the synapse: Shaft versus spine.

The ability of neurons to communicate and store information depends on the activity of synapses which can be located on small protrusions (dendritic spines) or directly on the dendritic shaft. The formation, plasticity, and stability of synapses are regulated by the neuronal cytoskeleton. Actin filaments together with microtubules, neurofilaments, septins, and scaffolding proteins orchestrate the structural organization of both shaft and spine synapses, enabling their efficacy in response to synaptic activation.

Nuclear Receptor Nr4a1 Regulates Striatal Striosome Development and Dopamine D Receptor Signaling.

The GABAergic medium-size spiny neuron (MSN), the striatal output neuron, may be classified into striosome, also known as patch, and matrix, based on neurochemical differences between the two compartments. At this time, little is known regarding the regulation of the development of the two compartments. , primarily described as a nuclear receptor/immediate early gene involved in the homeostasis of the dopaminergic system, is a striosomal marker.

Correction: Integrative approach to sporadic Alzheimer's disease: deficiency of TYROBP in cerebral Aβ amyloidosis mouse normalizes clinical phenotype and complement subnetwork molecular pathology without reducing Aβ burden.

This article was originally published under standard licence, but has now been made available under a CC BY 4.0 license. The PDF and HTML versions of the paper have been modified accordingly.

Integrative approach to sporadic Alzheimer's disease: deficiency of TYROBP in cerebral Aβ amyloidosis mouse normalizes clinical phenotype and complement subnetwork molecular pathology without reducing Aβ burden.

Integrative gene network approaches enable new avenues of exploration that implicate causal genes in sporadic late-onset Alzheimer's disease (LOAD) pathogenesis, thereby offering novel insights for drug-discovery programs. We previously constructed a probabilistic causal network model of sporadic LOAD and identified TYROBP/DAP12, encoding a microglial transmembrane signaling polypeptide and direct adapter of TREM2, as the most robust key driver gene in the network. Here, we show that absence of TYROBP/DAP12 in a mouse model of AD-type cerebral Aβ amyloidosis (APP/PSEN1) recapitulates the expected network characteristics by normalizing the transcriptome of APP/PSEN1 mice and repressing the induction of genes involved in the switch from homeostatic microglia to disease-associated microglia (DAM), including Trem2, complement (C1qa, C1qb, C1qc, and Itgax), Clec7a and Cst7.

Integrative approach to sporadic Alzheimer's disease: deficiency of TYROBP in a tauopathy mouse model reduces C1q and normalizes clinical phenotype while increasing spread and state of phosphorylation of tau.

TYROBP/DAP12 forms complexes with ectodomains of immune receptors (TREM2, SIRPβ1, CR3) associated with Alzheimer's disease (AD) and is a network hub and driver in the complement subnetwork identified by multi-scale gene network studies of postmortem human AD brain. Using transgenic or viral approaches, we characterized in mice the effects of TYROBP deficiency on the phenotypic and pathological evolution of tauopathy. Biomarkers usually associated with worsening clinical phenotype (i.

Deficiency of TYROBP, an adapter protein for TREM2 and CR3 receptors, is neuroprotective in a mouse model of early Alzheimer's pathology.

Conventional genetic approaches and computational strategies have converged on immune-inflammatory pathways as key events in the pathogenesis of late onset sporadic Alzheimer's disease (LOAD). Mutations and/or differential expression of microglial specific receptors such as TREM2, CD33, and CR3 have been associated with strong increased risk for developing Alzheimer's disease (AD). DAP12 (DNAX-activating protein 12)/TYROBP, a molecule localized to microglia, is a direct partner/adapter for TREM2, CD33, and CR3.

APP and APLP2 interact with the synaptic release machinery and facilitate transmitter release at hippocampal synapses.

The amyloid precursor protein (APP), whose mutations cause familial Alzheimer's disease, interacts with the synaptic release machinery, suggesting a role in neurotransmission. Here we mapped this interaction to the NH2-terminal region of the APP intracellular domain. A peptide encompassing this binding domain -named JCasp- is naturally produced by a γ-secretase/caspase double-cut of APP.

Reduced brain levels of DHEAS in hepatic coma patients: significance for increased GABAergic tone in hepatic encephalopathy.

Increased neurosteroids with allosteric modulatory activity on GABA(A) receptors such as 3α-5α tertrahydroprogesterone; allopregnanolone (ALLO), are candidates to explain the phenomenon of "increased GABAergic tone" in hepatic encephalopathy (HE). However, it is not known how changes of other GABA(A) receptor modulators such as dehydroepiandrosterone sulfate (DHEAS) contribute to altered GABAergic tone in HE. Concentrations of DHEAS were measured by radioimmunoassay in frontal cortex samples obtained at autopsy from 11 cirrhotic patients who died in hepatic coma and from an equal number of controls matched for age, gender, and autopsy delay intervals free from hepatic or neurological diseases.