Publications by authors named "Justin A MacDonald"

The inflammasome-forming NOD-like receptor containing pyrin-3 (NLRP3) protein is a critical player in the innate immune responses to cellular danger signals. New structural data of NLRP3 provide a framework to probe the conformational impact of nucleotide binding. In this study, microsecond molecular dynamics (MD) simulations were used to detail information on the unique structural conformations adopted by NLRP3 with ATP or ADP binding.

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The nucleotide oligomerization domain (NOD)-like receptors containing pyrin (NLRP) family of cytosolic pattern-recognition receptors play an integral role in host defense following exposure to a diverse set of pathogenic and sterile threats. The canonical event following ligand recognition is the formation of a heterooligomeric signaling complex termed the inflammasome that produces pro-inflammatory cytokines. Dysregulation of this process is associated with many autoimmune, cardiovascular, metabolic, and neurodegenerative diseases.

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Zipper-interacting protein kinase (ZIPK) is a Ser/Thr protein kinase with regulatory involvement in vascular smooth muscle cell (VSMC) actin polymerization and focal adhesion assembly dynamics. ZIPK silencing can induce cytoskeletal remodeling with disassembly of actin stress fiber networks and coincident loss of focal adhesion kinase (FAK)-pY397 phosphorylation. The link between ZIPK inhibition and FAK phosphorylation is unknown, and critical interactor(s) and regulator(s) are not yet defined.

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ING1 is a chromatin targeting subunit of the Sin3a histone deacetylase (HDAC) complex that alters chromatin structure to subsequently regulate gene expression. We find that ING1 knockdown increases expression of Twist1, Zeb 1&2, Snai1, Bmi1 and TSHZ1 drivers of EMT, promoting EMT and cell motility. ING1 expression had the opposite effect, promoting epithelial cell morphology and inhibiting basal and TGF-β-induced motility in 3D organoid cultures.

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New Findings: What is the central question of this study? DAPK3 contributes to the Ca -sensitization of vascular smooth muscle contraction: does this protein kinase participate in the myogenic response of cerebral arteries? What is the main finding and its importance? Small molecule inhibitors of DAPK3 effectively block the myogenic responses of cerebral arteries. HS38-dependent changes to vessel constriction occur independent of LC20 phosphorylation, and therefore DAPK3 appears to operate via the actin cytoskeleton. A role for DAPK3 in the myogenic response was not previously reported, and the results support a potential new therapeutic target in the cerebrovascular system.

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In the field of EEG, researchers generally rely on rules of thumb, rather than a priori statistical calculations, when planning the number of trials to include in an ERP study. To aid in this practice, studies have tried to establish minimum numbers of trials required to reliably isolate ERPs. However, these guidelines do not necessarily apply across different study designs, as the reliability of an ERP waveform is not the same as the statistical power of a given experiment.

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Smoothelin-like 1 (SMTNL1) modulates the contractile performance of smooth muscle and thus has a key role in vascular homeostasis. Elevated vascular tone, recognized as a contributor to the development of progressive cardiac dysfunction, was previously found with SMTNL1 deletion. In this study, we assessed cardiac morphology and function of male and female, wild-type () and global SMTNL1 knockout () mice at 10 weeks of age.

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The family of death-associated protein kinases (DAPKs) and DAPK-related apoptosis-inducing protein kinases (DRAKs) act as molecular switches for a multitude of cellular processes, including apoptotic and autophagic cell death events. This review summarizes the mechanisms for kinase activity regulation and discusses recent molecular investigations of DAPK and DRAK family members in the intestinal epithelium. In general, recent literature convincingly supports the importance of this family of protein kinases in the homeostatic processes that govern the proper function of the intestinal epithelium.

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Background: Ulcerative colitis (UC) is a progressive disorder that elevates the risk of colon cancer development through a colitis-dysplasia-carcinoma sequence. Gene expression profiling of colitis-associated lesions obtained from patients with varied extents of UC can be mined to define molecular panels associated with colon cancer development.

Methods: Differential gene expression profiles of 3 UC clinical subtypes and healthy controls were developed for the GSE47908 microarray data set of healthy controls, left-sided colitis, pancolitis, and colitis-associated dysplasia (CAD) using limma R.

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Insulin resistance (InR) is manifested in skeletal muscle by decreased insulin-stimulated glucose uptake due to impaired insulin signaling and multiple post-receptor intracellular defects. Chronic glucose-induced insulin resistance leads to the activation of Ser/Thr kinases and elevated phosphorylation of insulin receptor substrate 1 (IRS1) on Ser residues. Phosphorylation of IRS1 triggers the dissociation of IRS1 and its downstream effector, phosphatidylinositol 3-kinase.

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Advances in high-throughput sequencing technologies now yield unprecedented volumes of OMICs data with opportunities to conduct systematic data analyses and derive novel biological insights. Here, we provide protocols to perform differential-expressed gene analysis of TCGA and GTEx RNA-Seq data from human cancers, complete integrative GO and network analyses with focus on clinical and survival data, and identify differential correlation of trait-associated biomarkers. For complete details on the use and execution of this protocol, please refer to Chen and MacDonald (2021).

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Aquaporin 4 (AQP4) is a water transporting, transmembrane channel protein that has important regulatory roles in maintaining cellular water homeostasis. Several other AQP proteins exhibit calmodulin (CaM)-binding properties, and CaM has recently been implicated in the cell surface localization of AQP4. The objective of the present study was to assess the CaM-binding properties of AQP4 in detail.

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Respiratory silicosis is a preventable occupational disease that develops secondary to the aspiration of crystalline silicon dioxide (silica) into the lungs, activation of the NLRP3 inflammasome, and IL-1β production. Cathepsin Z has been associated with the development of inflammation and IL-1β production; however, the mechanism of how cathepsin Z leads to IL-1β production is unknown. Here, the requirement for cathepsin Z in silicosis was determined using WT mice and mice deficient in cathepsin Z.

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Colon adenocarcinoma is a prevalent malignancy with significant mortality. Hence, the identification of molecular biomarkers with prognostic significance is important for improved treatment and patient outcomes. Clinical traits and RNA-Seq of 551 patient samples in the UCSC Toil Recompute Compendium of The Cancer Genome Atlas TARGET and Genotype Tissue Expression project datasets (primary_site = colon) were used for weighted gene co-expression network analysis to reveal the association between gene networks and cancer cell invasion.

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In the search for new chemical scaffolds able to afford NLRP3 inflammasome inhibitors, we used a pharmacophore-hybridization strategy by combining the structure of the acrylic acid derivative INF39 with the 1-(piperidin-4-yl)1,3-dihydro-2-benzo[d]imidazole-2-one substructure present in HS203873, a recently identified NLRP3 binder. A series of differently modulated benzo[d]imidazole-2-one derivatives were designed and synthesised. The obtained compounds were screened in vitro to test their ability to inhibit NLRP3-dependent pyroptosis and IL-1β release in PMA-differentiated THP-1 cells stimulated with LPS/ATP.

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The pryin domain (PYD) domain is involved in protein interactions that lead to assembly of immune-sensing complexes such as inflammasomes. The repertoire of PYD-containing genes expressed by a cell type arms tissues with responses against a range of stimuli. The transcriptional regulation of the PYD gene family however is incompletely understood.

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The prototypical model for NOD-like receptor (NLR) inflammasome assembly includes nucleotide-dependent activation of the NLR downstream of pathogen- or danger-associated molecular pattern (PAMP or DAMP) recognition, followed by nucleation of hetero-oligomeric platforms that lie upstream of inflammatory responses associated with innate immunity. As members of the STAND ATPases, the NLRs are generally thought to share a similar model of ATP-dependent activation and effect. However, recent observations have challenged this paradigm to reveal novel and complex biochemical processes to discern NLRs from other STAND proteins.

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Swelling of the brain or spinal cord (CNS edema) affects millions of people every year. All potential pharmacological interventions have failed in clinical trials, meaning that symptom management is the only treatment option. The water channel protein aquaporin-4 (AQP4) is expressed in astrocytes and mediates water flux across the blood-brain and blood-spinal cord barriers.

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Speech comprehension is often thought of as an entirely auditory process, but both normal hearing and hearing-impaired individuals sometimes use visual attention to disambiguate speech, particularly when it is difficult to hear. Many studies have investigated how visual attention (or the lack thereof) impacts the perception of simple speech sounds such as isolated consonants, but there is a gap in the literature concerning visual attention during speech comprehension. This issue needs to be addressed, as individuals process sounds and words in everyday speech differently than when they are separated into individual elements with no competing sound sources or noise.

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Myosin regulatory light chain (LC20) phosphorylation plays an important role in vascular smooth muscle contraction and cell migration. Ca2+/calmodulin-dependent myosin light chain kinase (MLCK) phosphorylates LC20 (its only known substrate) exclusively at S19. Rho-associated kinase (ROCK) and zipper-interacting protein kinase (ZIPK) have been implicated in the regulation of LC20 phosphorylation via direct phosphorylation of LC20 at T18 and S19 and indirectly via phosphorylation of MYPT1 (the myosin targeting subunit of myosin light chain phosphatase, MLCP) and Par-4 (prostate-apoptosis response-4).

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Incomplete block designs are experimental designs in which a subset of treatments are included in each block. The researcher must decide which conditions are assigned to each block. This design concept is quite general.

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Objective: The effectiveness of three types of in-vehicle warnings was assessed in a driving simulator across different noise conditions.

Background: Although there has been much research comparing different types of warnings in auditory displays and interfaces, many of these investigations have been conducted in quiet laboratory environments with little to no consideration of background noise. Furthermore, the suitability of some auditory warning types, such as spearcons, as car warnings has not been investigated.

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The pregnane X receptor (PXR) is a ligand-activated nuclear receptor that acts as a xenobiotic sensor, responding to compounds of foreign origin, including pharmaceutical compounds, environmental contaminants, and natural products, to induce transcriptional events that regulate drug detoxification and efflux pathways. As such, the PXR is thought to play a key role in protecting the host from xenobiotic exposure. More recently, the PXR has been reported to regulate the expression of innate immune receptors in the intestine and modulate inflammasome activation in the vasculature.

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The pyrin domain containing Nod-like receptors (NLRPs) are a family of pattern recognition receptors known to regulate an array of immune signaling pathways. Emergent studies demonstrate the potential for regulatory control of inflammasome assembly by phosphorylation, notably NLRP3. Over a dozen phosphorylation sites have been identified for NLRP3 with many more suggested by phosphoproteomic studies of the NLRP family.

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