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Wells, S. E.

Publications and source records attributed to Wells, S. E..

3 recordsLinked to original sources

The Preclinical Animal Network (PCAN): Integrative high-throughput phenotyping of standardized mouse models for Prader-Willi syndrome

The Preclinical Animal Network (PCAN) is a collaborative resource established to advance translational research and therapeutic development for Prader-Willi syndrome (PWS), a rare neurodevelopmental disorder caused by loss of paternally expressed genes on chromosome 15q11-q13. PCAN integrates standardized, high-throughput phenotyping of approximately 1,000 mice across six engineered lines carrying paternal deletions of Ndn, Magel2, Snord116, Ipw, and multigenic loci. Using validated experimental pipelines spanning metabolic, behavioral, and developmental domains, we captured comprehensive phenotypic profiles by applying a statistical variance-decomposition framework to partition genetic and environmental contributions. This analysis provides robust genotype-phenotype maps, revealing shared and model-specific phenotypic effects while accounting for key confounding factors. The PCAN resource provides a framework for evaluating PWS-relevant phenotypes and benchmarking therapeutic strategies. By providing open access to its mouse models, datasets and analytical resources, PCAN enables the research community to apply standardized, reproducible workflows and accelerate the development of targeted, mechanism-based treatments.

genetics↗

Long-read transcriptomic identification of synaptic adaptation to amyloid pathology in the App(NL-G-F) knock-in mouse model of the earliest phase of Alzheimer's disease

Genome-wide association studies (GWAS) have identified a transcriptional network of Alzheimers disease (AD) risk genes that are primarily expressed in microglia and are associated with AD pathology. However, traditional short-read sequencers have limited our ability to fully characterize how GWAS variants exert their effects on gene expression regulation or alternative splicing in response to the pathology, particularly resulting in inaccurate detection of splicing. To address this gap, we utilized long-read RNA-sequencing (RNA-seq) in the AppNL-G-F knock-in mouse model to identify changes in splicing and novel transcript isoforms in response to amyloid-{beta}. We show that long-read RNA-seq can recapitulate the expected induction of microglial expressed risk genes such as Trem2 in response to amyloid-{beta} at 9 months of age associated with ageing-dependent deficiencies in spatial short-term memory in the AppNL-G-F knock-in mice. Our results not only identified novel splicing events and transcript isoform abundance in genes associated with AD, but also revealed the complex regulation of gene expression through splicing in response to amyloid plaques. Surprisingly, the regulation of alternative splicing in response to amyloid was seen in genes previously not identified as AD risk genes, expressed in microglia, neurons and oligodendrocytes, and included genes such as Syngr1 that modulate synaptic physiology. We saw alternative splicing in genes such as Ctsa, Clta, Dennd2a, Irf9 and Smad4 in mice in response to amyloid, and the orthologues of these genes also showed transcript usage changes in human AD brains. Our data suggests a model whereby induction of AD risk gene expression associated with microglial proliferation and activation is concomitant with alternative splicing in a different class of genes expressed by microglia and neurons, which act to adapt or preserve synaptic activity in response to amyloid-{beta} during early stages of the disease. Our study provides new insights into the mechanisms and effects of the regulation of genes associated with amyloid pathology, which may ultimately enable better disease diagnosis, and improved tracking of disease progression. Additionally, our findings identify new therapeutic avenues for treatment of AD.

genetics↗

Loss of Frrs1l disrupts synaptic AMPA receptor function, and results in neurodevelopmental, motor, cognitive and electrographical abnormalities

Summary statementIn this study, we show that the loss of the epilepsy-related gene Frrs1l in mice causes a dramatic reduction in AMPA receptor levels at the synapse. This change elicits severe motor and coordination disabilities, hyperactivity, cognitive defects, behavioural seizures and abnormal electroencephalographic (EEG) patterns.\n\nAbstractLoss of function mutations in the human AMPA receptor-associated protein, ferric chelate reductase 1-like (FRRS1L), are associated with a devastating neurological condition incorporating choreoathetosis, cognitive deficits and epileptic encephalopathies. Furthermore, evidence from overexpression and ex vivo studies have implicated FRRS1L in AMPA receptor biogenesis and assembly, suggesting that changes in glutamatergic signalling might underlie the disorder. Here, we investigated the neurological and neurobehavioural correlates of the disorder using a mouse Frrs1l null mutant. The study revealed several neurological defects that mirrored those seen in human patients. We established that mice lacking Frrs1l suffered from a broad spectrum of early-onset motor deficits with no progressive, age-related deterioration. Moreover, Frrs1l-/- mice were hyperactive irrespective of test environment, exhibited working memory deficits and displayed significant sleep fragmentation. Longitudinal electroencephalographic recordings also revealed abnormal EEG in Frrs1l-/- mice. Parallel investigations into disease aetiology identified a specific deficiency in AMPA receptor levels in the brain of Frrs1l-/- mice, while the general levels of several other synaptic components remained unchanged with no obvious alterations in the number of synapses. Furthermore, we established that Frrsl1 deletion results in glycosylation deficits in GLUA2 and GLUA4 AMPA receptor proteins, leading to cytoplasmic retention and a reduction of those specific AMPA receptor levels in the postsynaptic membrane. Overall, this study determines, for the first time in vivo, how loss of FRRS1L function can affect glutamatergic signalling and provides mechanistic insight into the development and progression of a human hyperkinetic disorder.

neuroscience↗