Publications by authors named "Scott A Shaffer"

Background: Perinatal depression (PND) is a debilitating condition affecting maternal well-being and child development. Allopregnanolone (ALLO) is important to perinatal neuroplasticity, however its relationship with depression severity and postpartum structural brain volume is unknown.

Method: We examined perinatal temporal dynamics and bidirectional associations between ALLO and depression severity and the association between these variables and postpartum gray matter volume, using a random intercept cross-lagged panel model.

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Parkinson's disease (PD) is the second most prevalent neurodegenerative disease and arises from dopamine (DA) neuron death selectively in the substantia nigra pars compacta (SNc). Rit2 is a reported PD risk allele, and recent single cell transcriptomic studies identified a major RIT2 cluster in PD DA neurons, potentially linking Rit2 expression loss to a PD patient cohort. However, it is still unknown whether Rit2 loss itself impacts DA neuron function and/or viability.

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Neuron-derived extracellular vesicles (NDEVs) are potential biomarkers of neurological diseases although their reliable molecular target is not well established. Here, we demonstrate that ATPase Na/K transporting subunit alpha 3 (ATP1A3) is abundantly expressed in extracellular vesicles (EVs) isolated from induced human neuron, brain, cerebrospinal fluid, and plasma in comparison with the presumed NDEV markers NCAM1 and L1CAM by using super-resolution microscopy and biochemical assessments. Proteomic analysis of immunoprecipitated ATP1A3 brain-derived EVs shows higher enrichment of synaptic markers and cargo proteins relevant to Alzheimer's disease (AD) compared to NCAM1 or LICAM EVs.

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Marine heatwaves cause widespread environmental, biological, and socio-economic impacts, placing them at the forefront of 21st-century management challenges. However, heatwaves vary in intensity and evolution, and a paucity of information on how this variability impacts marine species limits our ability to proactively manage for these extreme events. Here, we model the effects of four recent heatwaves (2014, 2015, 2019, 2020) in the Northeastern Pacific on the distributions of 14 top predator species of ecological, cultural, and commercial importance.

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Stimulator of interferon genes (STING) is an essential adaptor protein required for the inflammatory response to cytosolic DNA. dsDNA activates cGAS to generate cGAMP, which binds and activates STING triggering a conformational change, oligomerization, and the IRF3- and NFκB-dependent transcription of type I Interferons (IFNs) and inflammatory cytokines, as well as the activation of autophagy. Aberrant activation of STING is now linked to a growing number of both rare as well as common chronic inflammatory diseases.

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Seasonal "common-cold" human coronaviruses are widely spread throughout the world and are mainly associated with mild upper respiratory tract infections. The emergence of highly pathogenic coronaviruses MERS-CoV, SARS-CoV, and most recently SARS-CoV-2 has prompted increased attention to coronavirus biology and immunopathology, but the T-cell response to seasonal coronaviruses remains largely uncharacterized. Here we report the repertoire of viral peptides that are naturally processed and presented upon infection of a model cell line with seasonal coronavirus OC43.

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Plastic pollution is distributed patchily around the world's oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation.

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Proteins destined for the secretory compartment of the cell are cotranslationally translocated into the endoplasmic reticulum. The majority of these proteins are N-glycosylated, a co- and posttranslational modification that ensures proper protein folding, stability, solubility, and cellular localization. Here, we show that the [Formula: see text] subunit of the signal recognition particle receptor (SR) is required for assembly of the N-glycosylation-competent translocon.

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Unlabelled: Seasonal "common-cold" human coronaviruses are widely spread throughout the world and are mainly associated with mild upper respiratory tract infections. The emergence of highly pathogenic coronaviruses MERS-CoV, SARS-CoV, and most recently SARS-CoV-2 has prompted increased attention to coronavirus biology and immunopathology, but identification and characterization of the T cell response to seasonal human coronaviruses remain largely uncharacterized. Here we report the repertoire of viral peptides that are naturally processed and presented upon infection of a model cell line with seasonal human coronavirus OC43.

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Article Synopsis
  • * Two novel inhibitors, D-FFRCMKyne and D-FFCitCMKyne, effectively modify the M enzyme's active site, demonstrating unique binding and specificity, as they do not affect another cysteine protease involved in the virus's life cycle.
  • * These inhibitors have shown promising results in blocking SARS-CoV2 replication in lab cells and in tests on mice, indicating their potential as effective antiviral drugs against COVID-19.
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  • The study focuses on a rare amyloidogenic transthyretin (TTR) variant, T60I/V122I, in a 63-year-old African American woman with significant heart and nervous system issues.
  • The presence of two TTR mutations was confirmed through DNA sequencing, indicating compound heterozygosity, and both variants contributed to amyloid deposits found in the patient's tissue.
  • The findings suggest that while the T60I and V122I mutations have similar kinetic stabilities, their combination affects thermodynamic stability and amyloid growth in a way that is additive, not synergistic.
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Alzheimer's disease (AD) is a pervasive neurodegeneration disease with high heritability. In this study, we employed CRISPR-Cas9-engineered technology to investigate the effects of a rare mutation (rs144662445) in the A kinase anchoring protein 9 (AKAP9) gene, which is associated with AD in African Americans (AA), on tau pathology and the tau interactome in SH-SY5Y P301L neuron-like cells. The mutation significantly increased the level of phosphorylated tau, specifically at the site Ser396/Ser404.

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  • * This study explored the relationship between Mtb's carbon metabolism and drug interactions by using gene knockdown mutants to analyze the effects of common antitubercular drugs, revealing that the bacterial metabolic state significantly influences drug efficacy.
  • * The researchers identified ways to enhance rifampicin effectiveness when Mtb grows on cholesterol, providing insights that could help improve drug combinations and understanding of how laboratory results relate to real-world infection scenarios.
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Gene therapy is a potentially curative medicine for many currently untreatable diseases, and recombinant adeno-associated virus (rAAV) is the most successful gene delivery vehicle for in vivo applications. However, rAAV-based gene therapy suffers from several limitations, such as constrained DNA cargo size and toxicities caused by non-physiological expression of a transgene. Here we show that rAAV delivery of a suppressor tRNA (rAAV.

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Background: The sarcoglycan complex (SC) is part of a network that links the striated muscle cytoskeleton to the basal lamina across the sarcolemma. The SC coordinates changes in phosphorylation and Ca-flux during mechanical deformation, and these processes are disrupted with loss-of-function mutations in gamma-sarcoglycan (Sgcg) that cause Limb girdle muscular dystrophy 2C/R5.

Methods: To gain insight into how the SC mediates mechano-signaling in muscle, we utilized LC-MS/MS proteomics of SC-associated proteins in immunoprecipitates from enriched sarcolemmal fractions.

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  • Extracellular vesicles (EVs) play a crucial role in neurodegenerative diseases by transferring harmful molecules, impacting disease progression.
  • Researchers analyzed the protein profiles of EVs from four types of neural cells derived from human stem cells and identified specific protein markers unique to each cell type.
  • The study highlighted that astrocyte-specific EVs and their hub protein, integrin-β1, are significantly associated with Alzheimer’s disease pathology, providing important insights for future research on EV functions in neurodegenerative conditions.
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Mapping protein-protein interactions is crucial for understanding various signaling pathways in living cells, and developing new techniques for this purpose has attracted significant interest. Classic methods (e.g.

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Mammalian cells consume large amount of nutrients during growth and production. However, endogenous metabolic inefficiencies often prevent cells to fully utilize nutrients to support growth and protein production. Instead, significant fraction of fed nutrients is diverted into extracellular accumulation of waste by-products and metabolites, further inhibiting proliferation and protein synthesis.

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Citrullination is an enzyme-catalyzed post-translational modification (PTM) that is essential for a host of biological processes, including gene regulation, programmed cell death, and organ development. While this PTM is required for normal cellular functions, aberrant citrullination is a hallmark of autoimmune disorders as well as cancer. Although aberrant citrullination is linked to human pathology, the exact role of citrullination in disease remains poorly characterized, in part because of the challenges associated with identifying the specific arginine residues that are citrullinated.

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Methylmercury concentrations vary widely across geographic space and among habitat types, with marine and aquatic-feeding organisms typically exhibiting higher mercury concentrations than terrestrial-feeding organisms. However, there are few model organisms to directly compare mercury concentrations as a result of foraging in marine, estuarine, or terrestrial food webs. The ecological impacts of differential foraging may be especially important for generalist species that exhibit high plasticity in foraging habitats, locations, or diet.

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Alterations in the cGAS-STING DNA-sensing pathway affect intestinal homeostasis. We sought to delineate the functional role of STING in intestinal inflammation. Increased STING expression was a feature of intestinal inflammation in mice with colitis and in humans afflicted with inflammatory bowel disease.

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The amino acid sequences of proteins have evolved over billions of years, preserving their structures and functions while responding to evolutionary forces. Are there conserved sequence and structural elements that preserve the protein folding mechanisms? The functionally diverse and ancient (βα) TIM barrel motif may answer this question. We mapped the complex six-state folding free energy surface of a ∼3.

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Migratory marine species cross political borders and enter the high seas, where the lack of an effective global management framework for biodiversity leaves them vulnerable to threats. Here, we combine 10,108 tracks from 5775 individual birds at 87 sites with data on breeding population sizes to estimate the relative year-round importance of national jurisdictions and high seas areas for 39 species of albatrosses and large petrels. Populations from every country made extensive use of the high seas, indicating the stake each country has in the management of biodiversity in international waters.

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Article Synopsis
  • Inertial measurement units (IMUs), equipped with accelerometers and magnetometers, are crucial for analyzing the behavior of marine and terrestrial animals, requiring effective computational methods for managing large datasets.
  • This study deployed these sensors on free-ranging albatrosses and utilized unsupervised hidden Markov models (HMMs) to classify their behaviors into three categories: 'flapping flight', 'soaring flight', and 'on-water'.
  • Results showed that while accelerometer data alone was sufficient for accurate classification, incorporating magnetometer data enhanced the analysis of complex behaviors like dynamic soaring, highlighting the importance of developing efficient classification methodologies in behavioral research.
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Understanding the environmental and behavioral factors that influence how organisms maintain energy balance can inform us about their potential resiliency to rapid environmental changes. Flexibility in maintaining energy balance is particularly important to long-lived, central-place foraging seabirds that are constrained when locating food for offspring in a dynamic ocean environment. To understand the role of environmental interactions, behavioral flexibility and morphological constraints on energy balance, we used doubly labeled water to measure the at-sea daily energy expenditure (DEE) of two sympatrically breeding seabirds, Campbell () and grey-headed () albatrosses.

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