Unidentified Target Research Articles

Enhancing radiotherapy in triple-negative breast cancer with hesperetin-induced ferroptosis via AURKA targeting nanocomposites

Triple-negative breast cancer (TNBC) is an aggressive cancer type that lacks targeted treatment options. Ferroptosis, a novel therapeutic strategy, induces cell death by disrupting the oxidative-reductive balance. Hesperetin, a potential TNBC therapeutic drug, has unidentified regulatory targets. The objective of this study was to explore the potential targets of hesperetin in TNBC and investigate whether the nanocomposites carrier hesperetin-loaded ferroptosis-inducing nanocomposites (HFPN), which activates ferroptosis, can enhance the anti-tumor efficacy of hesperetin. Bioinformatics methods were employed to screen hesperetin targets in TNBC, and a molecular docking model between hesperetin and the core target aurora kinase A (AURKA) was successfully constructed. The stability and anti-tumor activity of HFPN were validated in cell and mouse models, including tumor suppression and increased radiation sensitivity. These results suggest that HFPN can regulate the core target AURKA in TNBC, disrupt tumor oxidative-reductive balance, promote ferroptosis in tumor cells, and ultimately enhance the effectiveness of radiation therapy for TNBC.Graphical abstract

A sex-dependent role of Kv1.3 channels from macrophages in metabolic syndrome.

Coronary artery disease (CAD) is the foremost single cause of mortality and disability globally. Patients with type 2 diabetes (T2DM) have a higher incidence of CAD, and poorer prognosis. The low-grade inflammation associated to T2DM contributes to increased morbidity and worst outcomes after revascularization. Inflammatory signaling in the vasculature supports endothelial dysfunction, leukocyte infiltration, and macrophage activation to a metabolic disease (MMe) specific phenotype, which could contribute to the metabolic disorders and ascular damage in T2DM. We have previously found that Kv1.3 blockers inhibit the development of intimal hyperplasia, thereby preventing restenosis. This inhibition was enhanced in a mouse model of T2DM, where systemic Kv1.3 blockers administration also improve metabolic dysfunction by acting on unidentified cellular targets other than vascular smooth muscle. Here we characterize the MMe phenotype in our T2DM model with a focus on macrophage Kv1.3 channels, to explore their contribution to vascular disease and their potential role as targets to ameliorate T2DM vascular risk. Male and female BPH mice fed on high-fat diet (HFD) develop metabolic syndrome (MetS) and T2DM. mRNA levels of several K+ channels (KV1.3, KCa3.1, Kir2.1) and macrophage markers (TNFα, NOS2, CD36) were analyzed. The MMe phenotype associated with increased CD36 expression. Channel-specific fingerprinting highlights a gender-specific increase of KV1.3 mRNA fold change in LPS stimulated macrophages from HFD compared to standard diet (SD). KV1.3 functional expression was also significantly increased after LPS stimulation in female HFD macrophages compared to SD. Functional studies showed that macrophage's KV1.3 channels of BPH female mice did not contribute to phagocytosis or metabolic profile but were relevant in cell migration rate. Altogether, our data suggest that by inhibiting macrophage infiltration, Kv1.3 blockers could contribute to disrupt the vicious cycle of inflammation and insulin resistance, offering a novel approach to prevent MetS, T2DM and its associated cardiovascular complications in females.

Mapping snoRNA-target RNA interactions in an RNA binding protein-dependent manner with chimeric eCLIP.

Small nucleolar RNAs (snoRNAs) are non-coding RNAs that function in ribosome and spliceosome biogenesis, primarily by guiding modifying enzymes to specific sites on ribosomal RNA (rRNA) and spliceosomal RNA (snRNA). However, many orphan snoRNAs remain uncharacterized, with unidentified or unvalidated targets, and studies on additional snoRNA-associated proteins are limited. We adapted an enhanced chimeric eCLIP approach to comprehensively profile snoRNA-target RNA interactions using both core and accessory snoRNA binding proteins as baits. Using core snoRNA binding proteins, we confirmed most annotated snoRNA-rRNA and snoRNA-snRNA interactions in mouse and human cell lines and called novel, high-confidence interactions for orphan snoRNAs. While some of these interactions result in chemical modification, others may have modification-independent functions. We then showed that snoRNA ribonucleoprotein complexes containing certain accessory proteins, like WDR43 and NOLC1, enriched for specific subsets of snoRNA-target RNA interactions with distinct roles in ribosome and spliceosome biogenesis. Notably, we discovered that SNORD89 guides 2'-O-methylation at two neighboring sites in U2 snRNA that are important for activating splicing, but also appear to ensure imperfect splicing for a subset of near-constitutive exons. Thus, chimeric eCLIP of snoRNA-associating proteins enables a comprehensive framework for studying snoRNA-target interactions in an RNA binding protein-dependent manner, revealing novel interactions and regulatory roles in RNA biogenesis.

The RNA-binding protein Nab2 regulates levels of the RhoGEF Trio to govern axon and dendrite morphology.

The Drosophila RNA-binding protein (RBP) Nab2 acts in neurons to regulate neurodevelopment and is orthologous to the human intellectual disability-linked RBP, ZC3H14. Nab2 governs axon projection in mushroom body neurons and limits dendritic arborization of class IV sensory neurons in part by regulating splicing events in ∼150 mRNAs. Analysis of the Sex-lethal (Sxl) mRNA revealed that Nab2 promotes an exon-skipping event and regulates m6A methylation on Sxl pre-mRNA by the Mettl3 methyltransferase. Mettl3 heterozygosity broadly rescues Nab2null phenotypes implying that Nab2 acts through similar mechanisms on other RNAs, including unidentified targets involved in neurodevelopment. Here, we show that Nab2 and Mettl3 regulate the removal of a 5'UTR (untranslated region) intron in the trio pre-mRNA. Trio utilizes two GEF domains to balance Rac and RhoGTPase activity. Intriguingly, an isoform of Trio containing only the RhoGEF domain, GEF2, is depleted in Nab2null nervous tissue. Expression of Trio-GEF2 rescues projection defects in Nab2null axons and dendrites, while the GEF1 Rac1-regulatory domain exacerbates these defects, suggesting Nab2-mediated regulation Trio-GEF activities. Collectively, these data indicate that Nab2-regulated processing of trio is critical for balancing Trio-GEF1 and -GEF2 activity and show that Nab2, Mettl3, and Trio function in a common pathway that shapes axon and dendrite morphology.

Two genome-wide interaction loci modify the association of nonsteroidal anti-inflammatory drugs with colorectal cancer.

Regular, long-term aspirin use may act synergistically with genetic variants, particularly those in mechanistically relevant pathways, to confer a protective effect on colorectal cancer (CRC) risk. We leveraged pooled data from 52 clinical trial, cohort, and case-control studies that included 30,806 CRC cases and 41,861 controls of European ancestry to conduct a genome-wide interaction scan between regular aspirin/nonsteroidal anti-inflammatory drug (NSAID) use and imputed genetic variants. After adjusting for multiple comparisons, we identified statistically significant interactions between regular aspirin/NSAID use and variants in 6q24.1 (top hit rs72833769), which has evidence of influencing expression of TBC1D7 (a subunit of the TSC1-TSC2 complex, a key regulator of MTOR activity), and variants in 5p13.1 (top hit rs350047), which is associated with expression of PTGER4 (codes a cell surface receptor directly involved in the mode of action of aspirin). Genetic variants with functional impact may modulate the chemopreventive effect of regular aspirin use, and our study identifies putative previously unidentified targets for additional mechanistic interrogation.

Network pharmacology study to explore the multiple molecular mechanism of SH003 in the treatment of non-small cell lung cancer

BackgroundNon-small cell lung cancer (NSCLC) is one of the leading causes of human death worldwide. Herbal prescription SH003 has been developed to treat several cancers including NSCLC. Due to the multi-component nature of SH003 with multiple targets and pathways, a network pharmacology study was conducted to analyze its active compounds, potential targets, and pathways for the treatment of NSCLC.MethodsWe systematically identified oral active compounds within SH003, employing ADME criteria-based screening from TM-MC, OASIS, and TCMSP databases. Concurrently, SH003-related and NSCLC-associated targets were amalgamated from various databases. Overlapping targets were deemed anti-NSCLC entities of SH003. Protein–protein interaction networks were constructed using the STRING database, allowing the identification of pivotal proteins through node centrality measures. Empirical validation was pursued through LC–MS analysis of active compounds. Additionally, in vitro experiments, such as MTT cell viability assays and western blot analyses, were conducted to corroborate network pharmacology findings.ResultsWe discerned 20 oral active compounds within SH003 and identified 239 core targets shared between SH003 and NSCLC-related genes. Network analyses spotlighted 79 hub genes, including TP53, JUN, AKT1, STAT3, and MAPK3, crucial in NSCLC treatment. GO and KEGG analyses underscored SH003’s multifaceted anti-NSCLC effects from a genetic perspective. Experimental validations verified SH003’s impact on NSCLC cell viability and the downregulation of hub genes. LC–MS analysis confirmed the presence of four active compounds, namely hispidulin, luteolin, baicalein, and chrysoeriol, among the eight compounds with a median of > 10 degrees in the herb-compounds-targets network in SH003. Previously unidentified targets like CASP9, MAPK9, and MCL1 were unveiled, supported by existing NSCLC literature, enhancing the pivotal role of empirical validation in network pharmacology.ConclusionOur study pioneers the harmonization of theoretical predictions with practical validations. Empirical validation illuminates specific SH003 compounds within NSCLC, simultaneously uncovering novel targets for NSCLC treatment. This integrated strategy, accentuating empirical validation, establishes a paradigm for in-depth herbal medicine exploration. Furthermore, our network pharmacology study unveils fresh insights into SH003’s multifaceted molecular mechanisms combating NSCLC. Through this approach, we delineate active compounds of SH003 and target pathways, reshaping our understanding of its therapeutic mechanisms in NSCLC treatment.

Discovery of potent thiazolidin-4-one sulfone derivatives for inhibition of proliferation of osteosarcoma in vitro and in vivo

Chemotherapy combining with surgical treatment has been the main strategy for osteosarcoma treatment in clinical. Due to unclear pathogenesis and unidentified drug targets, significant progress has not been made in the development of targeted drugs for osteosarcoma during the past 50 years. Our previous discovery reported compound R-8i with a high potency for the treatment of osteosarcoma by phenotypic screening. However, both the metabolic stability and bioavailability of R-8i are poor (T1/2 = 5.36 min, mouse liver microsome; and bioavailability in vivo F = 52.1 %, intraperitoneal administration) which limits it use for further drug development. Here, we described an extensive structure−activity relationship study of thiazolidine-4-one sulfone inhibitors from R-8i, which led to the discovery of compound 68. Compound 68 had a potent cellular activity with an IC50 value of 0.217 μM, much higher half-life (T1/2 = 73.8 min, mouse liver microsome) and an excellent pharmacokinetic profile (in vivo bioavailability F = 115 %, intraperitoneal administration). Compound 68 also showed good antitumor effects and low toxicity in a xenograft model (44.6 % inhibition osteosarcoma growth in BALB/c mice). These results suggest that compound 68 is a potential drug candidate for the treatment of osteosarcoma.

Chromosome 8p engineering reveals increased metastatic potential targetable by patient-specific synthetic lethality in liver cancer.

Large-scale chromosomal aberrations are prevalent in human cancer, but their function remains poorly understood. We established chromosome-engineered hepatocellular carcinoma cell lines using CRISPR-Cas9 genome editing. A 33-mega-base pair region on chromosome 8p (chr8p) was heterozygously deleted, mimicking a frequently observed chromosomal deletion. Using this isogenic model system, we delineated the functional consequences of chr8p loss and its impact on metastatic behavior and patient survival. We found that metastasis-associated genes on chr8p act in concert to induce an aggressive and invasive phenotype characteristic for chr8p-deleted tumors. Genome-wide CRISPR-Cas9 viability screening in isogenic chr8p-deleted cells served as a powerful tool to find previously unidentified synthetic lethal targets and vulnerabilities accompanying patient-specific chromosomal alterations. Using this target identification strategy, we showed that chr8p deletion sensitizes tumor cells to targeting of the reactive oxygen sanitizing enzyme Nudix hydrolase 17. Thus, chromosomal engineering allowed for the identification of novel synthetic lethalities specific to chr8p loss of heterozygosity.

2-Methyl-4-chlorophenoxyacetic acid (MCPA) sorption and desorption as a function of biochar properties and pyrolysis temperature.

2-Methyl-4-chlorophenoxyacetic acid (MCPA) is a highly mobile herbicide that is frequently detected in global potable water sources. One potential mitigation strategy is the sorption on biochar to limit harm to unidentified targets. However, irreversible sorption could restrict bioefficacy thereby compromising its usefulness as a vital crop herbicide. This research evaluated the effect of pyrolysis temperatures (350, 500 and 800°C) on three feedstocks; poultry manure, rice hulls and wood pellets, particularly to examine effects on the magnitude and reversibility of MCPA sorption. Sorption increased with pyrolysis temperature from 350 to 800°C. Sorption and desorption coefficients were strongly corelated with each other (R2 = 0.99; P < .05). Poultry manure and rice hulls pyrolyzed at 800°C exhibited irreversible sorption while for wood pellets at 800°C desorption was concentration dependent. At higher concentrations some desorption was observed (36% at 50 ppm) but was reduced at lower concentrations (1-3% at < 5 ppm). Desorption decreased with increasing pyrolysis temperature. Sorption data were analyzed with Langmuir, Freundlich, Dubinin-Radushkevich and Temkin isotherm models. Freundlich isotherms were better predictors of MCPA sorption (R2 ranging from 0.78 to 0.99). Poultry manure and rice hulls when pyrolyzed at higher temperatures (500 and 800°C) could be used for remediation efforts (such as spills or water filtration), due to the lack of desorption observed. On the other hand, un-pyrolyzed feedstocks or biochars created at 350°C could perform superior for direct field applications to limit indirect losses including runoff and leaching, since these materials also possess the ability to release MCPA subsequently to potentially allow herbicidal action.

Efficient genome editing in erythroid cells unveils novel MYB target genes and regulatory functions

Targeted genome editing holds great promise in biology. However, efficient genome modification, including gene knock-in (KI), remains an unattained goal in multiple cell types and loci due to poor transfection efficiencies and low target genes expression, impeding the positive selection of recombined cells. Here, we describe a genome editing approach to achieve efficient gene targeting using hard to transfect erythroid cell lines. We demonstrate robust fluorescent protein KI efficiency in low expressed transcription factor (TF) genes (e.g., Myb or Zeb1). We further show the ability to target two independent loci in individual cells, exemplified by MYB-GFP and NuMA-Cherry double KI, allowing multicolor labeling of regulatory factors at physiological endogenous levels. Our KI tagging approach allowed us to perform genome-wide TF analysis at increased signal-to-noise ratios, and highlighted previously unidentified MYB target genes and pathways. Overall, we establish a versatile CRISPR-Cas9-based platform, offering attractive opportunities for the dissection of the erythroid differentiation process.

Increased 3-O-sulfated heparan sulfate in Alzheimer's disease brain is associated with genetic risk gene HS3ST1.

HS3ST1 is a genetic risk gene associated with Alzheimer's disease (AD) and overexpressed in patients, but how it contributes to the disease progression is unknown. We report the analysis of brain heparan sulfate (HS) from AD and other tauopathies using a LC-MS/MS method. A specific 3-O-sulfated HS displayed sevenfold increase in the AD group (n = 14, P < 0.0005). Analysis of the HS modified by recombinant sulfotransferases and HS from genetic knockout mice revealed that the specific 3-O-sulfated HS is made by 3-O-sulfotransferase isoform 1 (3-OST-1), which is encoded by the HS3ST1 gene. A synthetic tetradecasaccharide (14-mer) carrying the specific 3-O-sulfated domain displayed stronger inhibition for tau internalization than a 14-mer without the domain, suggesting that the 3-O-sulfated HS is used in tau cellular uptake. Our findings suggest that the overexpression of HS3ST1 gene may enhance the spread of tau pathology, uncovering a previously unidentified therapeutic target for AD.

HDAC3 is critical in tumor development and therapeutic resistance in Kras-mutant non-small cell lung cancer.

HDAC3 is one of the main targets of histone deacetylase (HDAC) inhibitors in clinical development as cancer therapies, yet the in vivo role of HDAC3 in solid tumors is unknown. We identified a critical role for HDAC3 in Kras-mutant lung cancer. Using genetically engineered mouse models (GEMMs), we found that HDAC3 is required for lung tumor growth in vivo. HDAC3 was found to direct and enhance the transcription effects of the lung cancer lineage transcription factor NKX2-1 to mediate expression of a common set of target genes. We identified FGFR1 as a critical previously unidentified target of HDAC3. Leveraging this, we identified that an HDAC3-dependent transcriptional cassette becomes hyperactivated as Kras/LKB1-mutant cells develop resistance to the MEK inhibitor trametinib, and this can be reversed by treatment with the HDAC1/HDAC3 inhibitor entinostat. We found that the combination of entinostat plus trametinib treatment elicits therapeutic benefit in the Kras/LKB1 GEMM.

Robust Vision-Based Sliding Mode Control for Uncooperative Ground Target Searching and Tracking by Quadrotor

In this paper, the problem of searching and tracking uncooperative and unidentified mobile ground target using a quadcopter unmanned aerial vehicle (QUAV) is investigated. The proposed strategy is an Image-Based Visual Servoing (IBVS) approach, combined with the virtual camera concept and robust control. This strategy makes use of the rough prior information of the target, in contrast with existing strategies, which will alleviate the problem of altitude estimation noise and enhance the overall accuracy. Hence, a new vision-based sliding mode controller (SMC) is designed to control the quadcopter taking into account the flight phase’s heterogeneity, the external disturbances and parameters uncertainties as well as the target maneuverability. In order to get a better insight about the SMC tuning and adjustment, three different reaching laws are evaluated and compared. The proposed controller allows an automatic execution of the flight strategy whilst the searching phase relies on the Camera Coverage Area (CCA) technique. The vision-based technique allows an automatic QUAV altitude tuning for optimal target observation and tracking. Another contribution of this work is the fact that the designed controller validity and stability overspan the entire scenario to reach the universal and to smoothen out surges generated by control switching. Numerical simulations are conducted to compare the proposed SMC controllers and validate the effectiveness of the whole strategy.

On the relationship between tip-of-the-tongue states and partial recollective experience: Illusory partial recollective access during tip-of-the-tongue states.

Most people have experienced the sensation of having a word on the tip of the tongue. A common assumption is that a major driving force underlying the tip-of-the-tongue (TOT) state is conscious partial recollective access to some of the unretrieved word's attributes, such as its first letter. In the present study, under free-report conditions, participants provided more partial recollection responses during TOTs than non-TOTs without being more accurate among their provided responses. Under forced-guessing conditions in which participants needed to guess at the unidentified target word's first letter, participants exhibited false partial recollective experience during TOTs. This was shown by a strong tendency during TOTs to indicate that they knew the first letter, when in actuality, they were wrong in their first-letter guess. An additional experiment showed illusory partial recollection of a contextual detail during TOTs relative to non-TOTs. The full pattern of results portrays an alternative possible theoretical relationship between TOT states and subjective partial recollective experience. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Of Mice and Men and Plethysmography Systems: Does LKB1 Determine the Set Point of Carotid Body Chemosensitivity and the Hypoxic Ventilatory Response?

Our recent studies suggest that the level of liver kinase B1 (LKB1) expression in some way determines carotid body afferent discharge during hypoxia and to a lesser extent during hypercapnia. In short, phosphorylation by LKB1 of an as yet unidentified target(s) determines a set point for carotid body chemosensitivity. LKB1 is the principal kinase that activates the AMP-activated protein kinase (AMPK) during metabolic stresses, but conditional deletion of AMPK in catecholaminergic cells, including therein carotid body type I cells, has little or no effect on carotid body responses to hypoxia or hypercapnia. With AMPK excluded, the most likely target of LKB1 is one or other of the 12 AMPK-related kinases, which are constitutively phosphorylated by LKB1 and, in general, regulate gene expression. By contrast, the hypoxic ventilatory response is attenuated by either LKB1 or AMPK deletion in catecholaminergic cells, precipitating hypoventilation and apnea during hypoxia rather than hyperventilation. Moreover, LKB1, but not AMPK, deficiency causes Cheyne-Stokes-like breathing. This chapter will explore further the possible mechanisms that determine these outcomes.

Farmers’ Awareness and Perceptions in Agritourism Participation in Calaanan Bongabon Nueva Ecija: A basis of Marketing Development Plan

Agriculture is one of the top sources of livelihood of the residents of Calaanan Bongabon, Nueva Ecija, and since the area which is surrounded with great scenery, agritourism is slowly being introduced. With the potentials that agritourism has for the area and for the farmers, the researchers came to assess the awareness and perceptions of the farmers in agritourism participation in Calaanan, Bongabon, Nueva Ecija. The proponents derived the responses from twenty participants using quantitative research design. The result showed that there was high level of awareness to participate in agritourism specifically in awareness on the opportunity to develop connections to urban dwellers to rural culture and lifestyles. The farmers perceived agritourism as possible help to farmers to increase their standard of living. Moderate level of willingness to participate in agritourism was noted, this is due to challenges in lack of capital, the technical know-how on managing agritourism business, and unidentified target customers and others. This study has recommendations to address the challenges which may also be a basis of marketing development plan.

An insecticide target in mechanoreceptor neurons.

Hundreds of neurotoxic insecticides are currently in use. However, only a few direct targets have been identified. Here, using Drosophila and the insecticide flonicamid, we identified nicotinamidase (Naam) as a previous unidentified molecular target for an insecticide. Naam is expressed in chordotonal stretch-receptor neurons, and inhibition of Naam by a metabolite of flonicamid, TFNA-AM (4-trifluoromethylnicotinamide), induces accumulation of substrate nicotinamide and greatly inhibits negative geotaxis. Engineered flies harboring a point mutation in the active site show insecticide resistance and defects in gravity sensing. Bees are resistant to flonicamid because of a gene duplication, resulting in the generation of a TFNA-AM-insensitive Naam. Our results, in combination with the absence of genes encoding Naam in vertebrate genomes, suggest that TFNA-AM and potential species-specific Naam inhibitors could be developed as novel insecticides, anthelmintics, and antimicrobials for agriculture and human health.

Carbonic anhydrase 4 disruption decreases synaptic and behavioral adaptations induced by cocaine withdrawal.

Cocaine use followed by withdrawal induces synaptic changes in nucleus accumbens (NAc), which are thought to underlie subsequent drug-seeking behaviors and relapse. Previous studies suggest that cocaine-induced synaptic changes depend on acid-sensing ion channels (ASICs). Here, we investigated potential involvement of carbonic anhydrase 4 (CA4), an extracellular pH-buffering enzyme. We examined effects of CA4 in mice on ASIC-mediated synaptic transmission in medium spiny neurons (MSNs) in NAc, as well as on cocaine-induced synaptic changes and behavior. We found that CA4 is expressed in the NAc and present in synaptosomes. Disrupting CA4 either globally, or locally, increased ASIC-mediated synaptic currents in NAc MSNs and protected against cocaine withdrawal-induced changes in synapses and cocaine-seeking behavior. These findings raise the possibility that CA4 might be a previously unidentified therapeutic target for addiction and relapse.

Event-related potentials of food-induced blindness in the rapid serial visual presentation paradigm

Emotion-induced blindness is known as the impairment in the identification of targets that follow shortly after emotional distractors in the rapid serial visual presentation (RSVP) paradigm. Besides negative or erotic stimuli, food distractors have also been found to elicit a similar effect. This indicates an attentional bias for food stimuli in the temporal dimension of visual attention, which is highly relevant in the context of eating behaviour. So far, the neural mechanisms of this food-induced blindness are widely unknown. In the present study (N = 53), we investigated event-related potentials (ERPs) in response to food distractors and non-food targets in a single-target RSVP task. Automatic capture of visual attention by task-irrelevant food distractors was evident in enhanced Distractor Negativity (N2) and Early Food Positivity (P1). However, food distractors did not elicit a P3b. Thus, apparently, not the encoding of food distractors in working memory but alternative attentional processes are responsible for the food-induced blindness. Reduced target P3b reflected errors in target identification but was unaffected by the preceding distractor. In contrast, target N2 was specifically reduced for unidentified targets preceded by food distractors. Presumably, the attentional capture of food distractors may have caused a reduction of target N2, thereby contributing to the impairment in target identification. However, future research is needed to confirm this assumption and bridge the gap between the food-induced blindness on the behavioural level and the attentional capture of food stimuli reflected in the distractor ERPs.

Mechanism of stress-induced attacks in an episodic neurologic disorder.

Stress is the most common trigger among episodic neurologic disorders. In episodic ataxia type 2 (EA2), physical or emotional stress causes episodes of severe motor dysfunction that manifest as ataxia and dystonia. We used the tottering (tg/tg) mouse, a faithful animal model of EA2, to dissect the mechanisms underlying stress-induced motor attacks. We find that in response to acute stress, activation of α1-adrenergic receptors (α1-Rs) on Purkinje cells by norepinephrine leads to their erratic firing and consequently motor attacks. We show that norepinephrine induces erratic firing of Purkinje cells by disrupting their spontaneous intrinsic pacemaking via a casein kinase 2 (CK2)–dependent signaling pathway, which likely reduces the activity of calcium-dependent potassium channels. Moreover, we report that disruption of this signaling cascade at a number of nodes prevents stress-induced attacks in the tottering mouse. Together, our results suggest that norepinephrine and CK2 are required for the initiation of stress-induced attacks in EA2 and provide previously unidentified targets for therapeutic intervention.