The nuclear export signal mediates mutant atrophin-1-induced neuropathology in a mouse model of DRPLA.

Dentatorubral and pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disorder, caused by a CAG expansion in the atrophin-1 gene. The clinical features include chorea, ataxia, incoordination, emotional changes and dementia, progressing to early mortality. The atrophin-1 protein sequence contains a putative N-terminal nuclear localization signal (NLS) and a putative C-terminal nuclear export signal (NES).

Abnormal arteriolar blood volume measured by 3D inflow-based vascular-space-occupancy (iVASO) MRI and resting-state BOLD fluctuations at 7 T in individuals with recent-onset schizophrenia.

Background: We previously reported lower baseline arteriolar cerebral blood volumes (CBVa) in almost all gray matter regions in a cohort of individuals with schizophrenia of varying ages and disease duration. The extent to which decreased CBVa is also present in recent-onset schizophrenia, and how this impacts neurovascular coupling, remains to be determined. In this study, we sought to determine the extent of CBVa deficits in recent-onset schizophrenia and the relationship of CBVa to region-specific resting-state neural activity.

Protein aggregation identified in olfactory neuronal cells is associated with cognitive impairments in a subset of living schizophrenia patients.

Schizophrenia is a heterogeneous disorder, and likely results from multiple pathophysiological mechanisms. Protein aggregation, resulting from disruption of protein homeostasis (proteostasis), has been implicated in many diseases, including cancer, cardiac and pulmonary diseases, muscle diseases, and neurodegenerative disorders, but is a relatively new pathophysiological hypothesis for schizophrenia. Genetic findings implicate proteostasis in schizophrenia, and individual proteins associated with the disorder may undergo aggregation.

Huntingtin interactome reveals huntingtin role in regulation of double strand break DNA damage response (DSB/DDR), chromatin remodeling and RNA processing pathways.

Huntington's Disease (HD), a progressive neurodegenerative disorder with no disease-modifying therapies, is caused by a CAG repeat expansion in the HD gene encoding polyglutamine-expanded huntingtin (HTT) protein. Mechanisms of HD cellular pathogenesis and cellular functions of the normal and mutant HTT proteins are still not completely understood. HTT protein has numerous interaction partners, and it likely provides a scaffold for assembly of multiprotein complexes many of which may be altered in HD.

In vivo self-assembled siRNAs within small extracellular vesicles attenuate LRRK2-induced neurodegeneration in Parkinson's disease models.

Rationale: Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene play an important role in Parkinson's disease (PD) pathogenesis, and downregulation of LRRK2 has become a promising therapy for PD. Here, we developed a synthetic biology strategy for the self-assembly and delivery of small interfering RNAs (siRNAs) of LRRK2 into the substantia nigra via small extracellular vesicles (sEVs) using a genetic circuit (in the form of naked DNA plasmid) to attenuate PD-like phenotypes in mouse model.

Methods: We generated the genetic circuit encoding both a neuron-targeting rabies virus glycoprotein (RVG) tag and a LRRK2 siRNA under the control of a cytomegalovirus (CMV) promoter, and assessed its therapeutic effects using LRRK2 mouse models of PD.

Arginine methylation of RNA-binding proteins is impaired in Huntington's disease.

Huntington's disease (HD) is a progressive neurodegenerative disorder caused by a CAG repeat expansion in the HD gene, coding for huntingtin protein (HTT). Mechanisms of HD cellular pathogenesis remain undefined and likely involve disruptions in many cellular processes and functions presumably mediated by abnormal protein interactions of mutant HTT. We previously found HTT interaction with several protein arginine methyl-transferase (PRMT) enzymes.

Ankyrin-G Heterozygous Knockout Mice Display Increased Sensitivity to Social Defeat Stress.

The locus has been repeatedly found to confer an increased risk for bipolar disorder. codes for Ankyrin-G (Ank-G), a scaffold protein concentrated at axon initial segments, nodes of Ranvier, and dendritic spines, where it organizes voltage-gated sodium and potassium channels and cytoskeletal proteins. Mice with homozygous conditional knockout of Ank-G in the adult forebrain display hyperactivity and reduced anxiety-like behaviors, responsive to mood stabilizers.

Mutant VPS35-D620N induces motor dysfunction and impairs DAT-mediated dopamine recycling pathway.

The D620N mutation in vacuolar protein sorting protein 35 (VPS35) gene has been identified to be linked to late onset familial Parkinson disease (PD). However, the pathophysiological roles of VPS35-D620N in PD remain unclear. Here, we generated the transgenic Caenorhabditis elegans overexpressing either human wild type or PD-linked mutant VPS35-D620N in neurons.

A biological classification of Huntington's disease: the Integrated Staging System.

The current research paradigm for Huntington's disease is based on participants with overt clinical phenotypes and does not address its pathophysiology nor the biomarker changes that can precede by decades the functional decline. We have generated a new research framework to standardise clinical research and enable interventional studies earlier in the disease course. The Huntington's Disease Integrated Staging System (HD-ISS) comprises a biological research definition and evidence-based staging centred on biological, clinical, and functional assessments.

Amygdala and anterior cingulate transcriptomes from individuals with bipolar disorder reveal downregulated neuroimmune and synaptic pathways.

Recent genetic studies have identified variants associated with bipolar disorder (BD), but it remains unclear how brain gene expression is altered in BD and how genetic risk for BD may contribute to these alterations. Here, we obtained transcriptomes from subgenual anterior cingulate cortex and amygdala samples from post-mortem brains of individuals with BD and neurotypical controls, including 511 total samples from 295 unique donors. We examined differential gene expression between cases and controls and the transcriptional effects of BD-associated genetic variants.

Interaction of huntingtin with PRMTs and its subsequent arginine methylation affects HTT solubility, phase transition behavior and neuronal toxicity.

Huntington's disease (HD) is an incurable neurodegenerative disorder caused by a CAG expansion in the huntingtin gene (HTT). Post-translational modifications of huntingtin protein (HTT), such as phosphorylation, acetylation and ubiquitination, have been implicated in HD pathogenesis. Arginine methylation/dimethylation is an important modification with an emerging role in neurodegeneration; however, arginine methylation of HTT remains largely unexplored.

Curcumin Reduced HO- and G2385R-LRRK2-Induced Neurodegeneration.

Mutations in () are the most frequent genetic factors contributing to Parkinson's disease (PD). G2385R- increases the risk for PD susceptibility in the Chinese population. However, the pathological role of G2385R- is not clear.

Preventing amyotrophic lateral sclerosis: insights from pre-symptomatic neurodegenerative diseases.

Significant progress has been made in understanding the pre-symptomatic phase of amyotrophic lateral sclerosis. While much is still unknown, advances in other neurodegenerative diseases offer valuable insights. Indeed, it is increasingly clear that the well-recognized clinical syndromes of Alzheimer's disease, Parkinson's disease, Huntington's disease, spinal muscular atrophy and frontotemporal dementia are also each preceded by a pre-symptomatic or prodromal period of varying duration, during which the underlying disease process unfolds, with associated compensatory changes and loss of inherent system redundancy.

Immortalized striatal precursor neurons from Huntington's disease patient-derived iPS cells as a platform for target identification and screening for experimental therapeutics.

We have previously established induced pluripotent stem cell (iPSC) models of Huntington's disease (HD), demonstrating CAG-repeat-expansion-dependent cell biological changes and toxicity. However, the current differentiation protocols are cumbersome and time consuming, making preparation of large quantities of cells for biochemical or screening assays difficult. Here, we report the generation of immortalized striatal precursor neurons (ISPNs) with normal (33) and expanded (180) CAG repeats from HD iPSCs, differentiated to a phenotype resembling medium spiny neurons (MSN), as a proof of principle for a more tractable patient-derived cell model.

Huntingtin silencing delays onset and slows progression of Huntington's disease: a biomarker study.

Huntington's disease is a dominantly inherited, fatal neurodegenerative disorder caused by a CAG expansion in the huntingtin (HTT) gene, coding for pathological mutant HTT protein (mHTT). Because of its gain-of-function mechanism and monogenic aetiology, strategies to lower HTT are being actively investigated as disease-modifying therapies. Most approaches are currently targeted at the manifest stage, where clinical outcomes are used to evaluate the effectiveness of therapy.

Mutant-TMEM230-induced neurodegeneration and impaired axonal mitochondrial transport.

Parkinson's disease (PD) is a neurodegenerative disease with movement disorders including resting tremor, rigidity, bradykinesia and postural instability. Recent studies have identified a new PD associated gene, TMEM230 (transmembrane protein 230). However, the pathological roles of TMEM230 and its variants are not fully understood.

Huntingtin-mediated axonal transport requires arginine methylation by PRMT6.

The huntingtin (HTT) protein transports various organelles, including vesicles containing neurotrophic factors, from embryonic development throughout life. To better understand how HTT mediates axonal transport and why this function is disrupted in Huntington's disease (HD), we study vesicle-associated HTT and find that it is dimethylated at a highly conserved arginine residue (R118) by the protein arginine methyltransferase 6 (PRMT6). Without R118 methylation, HTT associates less with vesicles, anterograde trafficking is diminished, and neuronal death ensues-very similar to what occurs in HD.

A high-throughput screening to identify small molecules that suppress huntingtin promoter activity or activate huntingtin-antisense promoter activity.

Huntington's disease (HD) is a neurodegenerative disorder caused by a CAG repeat expansion in exon 1 of huntingtin (HTT). While there are currently no disease-modifying treatments for HD, recent efforts have focused on the development of nucleotide-based therapeutics to lower HTT expression. As an alternative to siRNA or oligonucleotide methods, we hypothesized that suppression of HTT expression might be accomplished by small molecules that either (1) directly decrease HTT expression by suppressing HTT promoter activity or (2) indirectly decrease HTT expression by increasing the promoter activity of HTT-AS, the gene antisense to HTT that appears to inhibit expression of HTT.