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Tau Phosphorylation At Alzheimer's Disease-Related Ser356 Contributes To Tau Stabilization When Par-1/Mark Activity Is Elevated., Kanae Ando, Mikiko Oka, Yosuke Ohtake, Motoki Hayashishita, Sawako Shimizu, Shin-Ichi Hisanaga, Koichi M. Iijima Sep 2016

Tau Phosphorylation At Alzheimer's Disease-Related Ser356 Contributes To Tau Stabilization When Par-1/Mark Activity Is Elevated., Kanae Ando, Mikiko Oka, Yosuke Ohtake, Motoki Hayashishita, Sawako Shimizu, Shin-Ichi Hisanaga, Koichi M. Iijima

Department of Neuroscience Faculty Papers

Abnormal phosphorylation of the microtubule-associated protein tau is observed in many neurodegenerative diseases, including Alzheimer's disease (AD). AD-related phosphorylation of two tau residues, Ser262 and Ser356, by PAR-1/MARK stabilizes tau in the initial phase of mismetabolism, leading to subsequent phosphorylation events, accumulation, and toxicity. However, the relative contribution of phosphorylation at each of these sites to tau stabilization has not yet been elucidated. In a Drosophila model of human tau toxicity, we found that tau was phosphorylated at Ser262, but not at Ser356, and that blocking Ser262 phosphorylation decreased total tau levels. By contrast, when PAR-1 was co-overexpressed with tau, …


Closed-State Inactivation Involving An Internal Gate In Kv4.1 Channels Modulates Pore Blockade By Intracellular Quaternary Ammonium Ions., Jeffrey D. Fineberg, Tibor G. Szanto, Gyorgy Panyi, Manuel Covarrubias Aug 2016

Closed-State Inactivation Involving An Internal Gate In Kv4.1 Channels Modulates Pore Blockade By Intracellular Quaternary Ammonium Ions., Jeffrey D. Fineberg, Tibor G. Szanto, Gyorgy Panyi, Manuel Covarrubias

Department of Neuroscience Faculty Papers

Voltage-gated K(+) (Kv) channel activation depends on interactions between voltage sensors and an intracellular activation gate that controls access to a central pore cavity. Here, we hypothesize that this gate is additionally responsible for closed-state inactivation (CSI) in Kv4.x channels. These Kv channels undergo CSI by a mechanism that is still poorly understood. To test the hypothesis, we deduced the state of the Kv4.1 channel intracellular gate by exploiting the trap-door paradigm of pore blockade by internally applied quaternary ammonium (QA) ions exhibiting slow blocking kinetics and high-affinity for a blocking site. We found that inactivation gating seemingly traps benzyl-tributylammonium …


Dcc Mediates Functional Assembly Of Peripheral Auditory Circuits., Young J Kim, Sheng-Zhi Wang, Stephen Tymanskyj, Le Ma, Huizhong W Tao, Li I Zhang Apr 2016

Dcc Mediates Functional Assembly Of Peripheral Auditory Circuits., Young J Kim, Sheng-Zhi Wang, Stephen Tymanskyj, Le Ma, Huizhong W Tao, Li I Zhang

Department of Neuroscience Faculty Papers

Proper structural organization of spiral ganglion (SG) innervation is crucial for normal hearing function. However, molecular mechanisms underlying the developmental formation of this precise organization remain not well understood. Here, we report in the developing mouse cochlea that deleted in colorectal cancer (Dcc) contributes to the proper organization of spiral ganglion neurons (SGNs) within the Rosenthal's canal and of SGN projections toward both the peripheral and central auditory targets. In Dcc mutant embryos, mispositioning of SGNs occurred along the peripheral auditory pathway with misrouted afferent fibers and reduced synaptic contacts with hair cells. The central auditory pathway simultaneously exhibited similar …


Stabilization Of Microtubule-Unbound Tau Via Tau Phosphorylation At Ser262/356 By Par-1/Mark Contributes To Augmentation Of Ad-Related Phosphorylation And Aβ42-Induced Tau Toxicity., Kanae Iijima-Ando, Akiko Maruko-Otake, Yosuke Ohtake, Motoki Hayashishita, Michiko Sekiya, Koichi M Iijima Mar 2016

Stabilization Of Microtubule-Unbound Tau Via Tau Phosphorylation At Ser262/356 By Par-1/Mark Contributes To Augmentation Of Ad-Related Phosphorylation And Aβ42-Induced Tau Toxicity., Kanae Iijima-Ando, Akiko Maruko-Otake, Yosuke Ohtake, Motoki Hayashishita, Michiko Sekiya, Koichi M Iijima

Department of Neuroscience Faculty Papers

Abnormal accumulation of the microtubule-interacting protein tau is associated with neurodegenerative diseases including Alzheimer's disease (AD). β-amyloid (Aβ) lies upstream of abnormal tau behavior, including detachment from microtubules, phosphorylation at several disease-specific sites, and self-aggregation into toxic tau species in AD brains. To prevent the cascade of events leading to neurodegeneration in AD, it is essential to elucidate the mechanisms underlying the initial events of tau mismetabolism. Currently, however, these mechanisms remain unclear. In this study, using transgenic Drosophila co-expressing human tau and Aβ, we found that tau phosphorylation at AD-related Ser262/356 stabilized microtubule-unbound tau in the early phase of …


Loss Of Vglut3 Produces Circadian-Dependent Hyperdopaminergia And Ameliorates Motor Dysfunction And L-Dopa-Mediated Dyskinesias In A Model Of Parkinson's Disease., Christopher B. Divito, Kathy Steece-Collier, Daniel T. Case, Sean-Paul G. Williams, Jennifer A. Stancati, Lianteng Zhi, Maria E. Rubio, Caryl E. Sortwell, Timothy J. Collier, David Sulzer, Robert H. Edwards, Hui Zhang, Rebecca P. Seal Nov 2015

Loss Of Vglut3 Produces Circadian-Dependent Hyperdopaminergia And Ameliorates Motor Dysfunction And L-Dopa-Mediated Dyskinesias In A Model Of Parkinson's Disease., Christopher B. Divito, Kathy Steece-Collier, Daniel T. Case, Sean-Paul G. Williams, Jennifer A. Stancati, Lianteng Zhi, Maria E. Rubio, Caryl E. Sortwell, Timothy J. Collier, David Sulzer, Robert H. Edwards, Hui Zhang, Rebecca P. Seal

Department of Neuroscience Faculty Papers

UNLABELLED: The striatum is essential for many aspects of mammalian behavior, including motivation and movement, and is dysfunctional in motor disorders such as Parkinson's disease. The vesicular glutamate transporter 3 (VGLUT3) is expressed by striatal cholinergic interneurons (CINs) and is thus well positioned to regulate dopamine (DA) signaling and locomotor activity, a canonical measure of basal ganglia output. We now report that VGLUT3 knock-out (KO) mice show circadian-dependent hyperlocomotor activity that is restricted to the waking cycle and is due to an increase in striatal DA synthesis, packaging, and release. Using a conditional VGLUT3 KO mouse, we show that deletion …


Interactions Of L-3,5,3′-Triiodothyronine, Allopregnanolone, And Ivermectin With The Gabaa Receptor: Evidence For Overlapping Intersubunit Binding Modes, Thomas Westergard, Reza Salari, Joseph V. Martin, Grace Brannigan Nov 2015

Interactions Of L-3,5,3′-Triiodothyronine, Allopregnanolone, And Ivermectin With The Gabaa Receptor: Evidence For Overlapping Intersubunit Binding Modes, Thomas Westergard, Reza Salari, Joseph V. Martin, Grace Brannigan

Department of Neuroscience Faculty Papers

No abstract provided.


Positive Allosteric Modulation Of Kv Channels By Sevoflurane: Insights Into The Structural Basis Of Inhaled Anesthetic Action., Qiansheng Liang, Warren D Anderson, Shelly T Jones, Caio S Souza, Juliana M Hosoume, Werner Treptow, Manuel Covarrubias Nov 2015

Positive Allosteric Modulation Of Kv Channels By Sevoflurane: Insights Into The Structural Basis Of Inhaled Anesthetic Action., Qiansheng Liang, Warren D Anderson, Shelly T Jones, Caio S Souza, Juliana M Hosoume, Werner Treptow, Manuel Covarrubias

Department of Neuroscience Faculty Papers

Inhalational general anesthesia results from the poorly understood interactions of haloethers with multiple protein targets, which prominently includes ion channels in the nervous system. Previously, we reported that the commonly used inhaled anesthetic sevoflurane potentiates the activity of voltage-gated K+ (Kv) channels, specifically, several mammalian Kv1 channels and the Drosophila K-Shaw2 channel. Also, previous work suggested that the S4-S5 linker of K-Shaw2 plays a role in the inhibition of this Kv channel by n-alcohols and inhaled anesthetics. Here, we hypothesized that the S4-S5 linker is also a determinant of the potentiation of Kv1.2 and K-Shaw2 by sevoflurane. Following functional expression …


Human Ips Cell-Derived Astrocyte Transplants Preserve Respiratory Function After Spinal Cord Injury., Ke Li, Elham Javed, Daniel Scura, Tamara J. Hala, Suneil Seetharam, Aditi Falnikar, Jean-Philippe Richard, Ashley Chorath, Nicholas J. Maragakis, Megan C. Wright, Angelo C. Lepore Sep 2015

Human Ips Cell-Derived Astrocyte Transplants Preserve Respiratory Function After Spinal Cord Injury., Ke Li, Elham Javed, Daniel Scura, Tamara J. Hala, Suneil Seetharam, Aditi Falnikar, Jean-Philippe Richard, Ashley Chorath, Nicholas J. Maragakis, Megan C. Wright, Angelo C. Lepore

Department of Neuroscience Faculty Papers

Transplantation-based replacement of lost and/or dysfunctional astrocytes is a promising therapy for spinal cord injury (SCI) that has not been extensively explored, despite the integral roles played by astrocytes in the central nervous system (CNS). Induced pluripotent stem (iPS) cells are a clinically-relevant source of pluripotent cells that both avoid ethical issues of embryonic stem cells and allow for homogeneous derivation of mature cell types in large quantities, potentially in an autologous fashion. Despite their promise, the iPS cell field is in its infancy with respect to evaluating in vivo graft integration and therapeutic efficacy in SCI models. Astrocytes express …


Taranis Functions With Cyclin A And Cdk1 In A Novel Arousal Center To Control Sleep In Drosophila., Dinis J.S. Afonso, Die Liu, Daniel R. Machado, Huihui Pan, James E.C. Jepson, Dragana Rogulja, Kyunghee Koh Jun 2015

Taranis Functions With Cyclin A And Cdk1 In A Novel Arousal Center To Control Sleep In Drosophila., Dinis J.S. Afonso, Die Liu, Daniel R. Machado, Huihui Pan, James E.C. Jepson, Dragana Rogulja, Kyunghee Koh

Department of Neuroscience Faculty Papers

Sleep is an essential and conserved behavior whose regulation at the molecular and anatomical level remains to be elucidated. Here, we identify TARANIS (TARA), a Drosophila homolog of the Trip-Br (SERTAD) family of transcriptional coregulators, as a molecule that is required for normal sleep patterns. Through a forward-genetic screen, we isolated tara as a novel sleep gene associated with a marked reduction in sleep amount. Targeted knockdown of tara suggests that it functions in cholinergic neurons to promote sleep. tara encodes a conserved cell-cycle protein that contains a Cyclin A (CycA)-binding homology domain. TARA regulates CycA protein levels and genetically …


Persistent At-Level Thermal Hyperalgesia And Tactile Allodynia Accompany Chronic Neuronal And Astrocyte Activation In Superficial Dorsal Horn Following Mouse Cervical Contusion Spinal Cord Injury., Jaime L Watson, Tamara J Hala, Rajarshi Putatunda, Daniel Sannie, Angelo C Lepore Sep 2014

Persistent At-Level Thermal Hyperalgesia And Tactile Allodynia Accompany Chronic Neuronal And Astrocyte Activation In Superficial Dorsal Horn Following Mouse Cervical Contusion Spinal Cord Injury., Jaime L Watson, Tamara J Hala, Rajarshi Putatunda, Daniel Sannie, Angelo C Lepore

Department of Neuroscience Faculty Papers

In humans, sensory abnormalities, including neuropathic pain, often result from traumatic spinal cord injury (SCI). SCI can induce cellular changes in the CNS, termed central sensitization, that alter excitability of spinal cord neurons, including those in the dorsal horn involved in pain transmission. Persistently elevated levels of neuronal activity, glial activation, and glutamatergic transmission are thought to contribute to the hyperexcitability of these dorsal horn neurons, which can lead to maladaptive circuitry, aberrant pain processing and, ultimately, chronic neuropathic pain. Here we present a mouse model of SCI-induced neuropathic pain that exhibits a persistent pain phenotype accompanied by chronic neuronal …


Defects In Synapse Structure And Function Precede Motor Neuron Degeneration In Drosophila Models Of Fus-Related Als., Mohammad Shahidullah, Sylvain J Le Marchand, Hong Fei, Jiaming Zhang, Udai Bhan Pandey, Matthew B. Dalva, Piera Pasinelli, Irwin B. Levitan Dec 2013

Defects In Synapse Structure And Function Precede Motor Neuron Degeneration In Drosophila Models Of Fus-Related Als., Mohammad Shahidullah, Sylvain J Le Marchand, Hong Fei, Jiaming Zhang, Udai Bhan Pandey, Matthew B. Dalva, Piera Pasinelli, Irwin B. Levitan

Department of Neuroscience Faculty Papers

Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disease that leads invariably to fatal paralysis associated with motor neuron degeneration and muscular atrophy. One gene associated with ALS encodes the DNA/RNA-binding protein Fused in Sarcoma (FUS). There now exist two Drosophila models of ALS. In one, human FUS with ALS-causing mutations is expressed in fly motor neurons; in the other, the gene cabeza (caz), the fly homolog of FUS, is ablated. These FUS-ALS flies exhibit larval locomotor defects indicative of neuromuscular dysfunction and early death. The locus and site of initiation of this neuromuscular dysfunction remain unclear. We show here …


Genetic And Anatomical Basis Of The Barrier Separating Wakefulness And Anesthetic-Induced Unresponsiveness., William J Joiner, Eliot B Friedman, Hsiao-Tung Hung, Kyunghee Koh, Mallory Sowcik, Amita Sehgal, Max B Kelz Sep 2013

Genetic And Anatomical Basis Of The Barrier Separating Wakefulness And Anesthetic-Induced Unresponsiveness., William J Joiner, Eliot B Friedman, Hsiao-Tung Hung, Kyunghee Koh, Mallory Sowcik, Amita Sehgal, Max B Kelz

Department of Neuroscience Faculty Papers

A robust, bistable switch regulates the fluctuations between wakefulness and natural sleep as well as those between wakefulness and anesthetic-induced unresponsiveness. We previously provided experimental evidence for the existence of a behavioral barrier to transitions between these states of arousal, which we call neural inertia. Here we show that neural inertia is controlled by processes that contribute to sleep homeostasis and requires four genes involved in electrical excitability: Sh, sss, na and unc79. Although loss of function mutations in these genes can increase or decrease sensitivity to anesthesia induction, surprisingly, they all collapse neural inertia. These effects are genetically selective: …


Expression Of C-Fos In Hilar Mossy Cells Of The Dentate Gyrus In Vivo., Aine M Duffy, Michael J Schaner, Jeannie Chin, Helen E Scharfman Aug 2013

Expression Of C-Fos In Hilar Mossy Cells Of The Dentate Gyrus In Vivo., Aine M Duffy, Michael J Schaner, Jeannie Chin, Helen E Scharfman

Department of Neuroscience Faculty Papers

Granule cells (GCs) of the dentate gyrus (DG) are considered to be quiescent--they rarely fire action potentials. In contrast, the other glutamatergic cell type in the DG, hilar mossy cells (MCs) often have a high level of spontaneous activity based on recordings in hippocampal slices. MCs project to GCs, so activity in MCs could play an important role in activating GCs. Therefore, we investigated whether MCs were active under basal conditions in vivo, using the immediate early gene c-fos as a tool. We hypothesized that MCs would exhibit c-fos expression even if rats were examined randomly, under normal housing conditions. …


Exploring Volatile General Anesthetic Binding To A Closed Membrane-Bound Bacterial Voltage-Gated Sodium Channel Via Computation., S G Raju, Annika F Barber, David N Lebard, Michael L Klein, Vincenzo Carnevale Jun 2013

Exploring Volatile General Anesthetic Binding To A Closed Membrane-Bound Bacterial Voltage-Gated Sodium Channel Via Computation., S G Raju, Annika F Barber, David N Lebard, Michael L Klein, Vincenzo Carnevale

Department of Neuroscience Faculty Papers

Despite the clinical ubiquity of anesthesia, the molecular basis of anesthetic action is poorly understood. Amongst the many molecular targets proposed to contribute to anesthetic effects, the voltage gated sodium channels (VGSCs) should also be considered relevant, as they have been shown to be sensitive to all general anesthetics tested thus far. However, binding sites for VGSCs have not been identified. Moreover, the mechanism of inhibition is still largely unknown. The recently reported atomic structures of several members of the bacterial VGSC family offer the opportunity to shed light on the mechanism of action of anesthetics on these important ion …


Serotonergic Innervation And Serotonin Receptor Expression Of Npy-Producing Neurons In The Rat Lateral And Basolateral Amygdaloid Nuclei., M Bonn, A Schmitt, K-P Lesch, E J Van Bockstaele, E Asan Mar 2013

Serotonergic Innervation And Serotonin Receptor Expression Of Npy-Producing Neurons In The Rat Lateral And Basolateral Amygdaloid Nuclei., M Bonn, A Schmitt, K-P Lesch, E J Van Bockstaele, E Asan

Department of Neuroscience Faculty Papers

Pharmacobehavioral studies in experimental animals, and imaging studies in humans, indicate that serotonergic transmission in the amygdala plays a key role in emotional processing, especially for anxiety-related stimuli. The lateral and basolateral amygdaloid nuclei receive a dense serotonergic innervation in all species studied to date. We investigated interrelations between serotonergic afferents and neuropeptide Y (NPY)-producing neurons, which are a subpopulation of inhibitory interneurons in the rat lateral and basolateral nuclei with particularly strong anxiolytic properties. Dual light microscopic immunolabeling showed numerous appositions of serotonergic afferents on NPY-immunoreactive somata. Using electron microscopy, direct membrane appositions and synaptic contacts between serotonin-containing axon …


Synchronous And Asynchronous Theta And Gamma Activity During Episodic Memory Formation., John F Burke, Kareem A Zaghloul, Joshua Jacobs, Ryan B Williams, Michael R Sperling, Ashwini D Sharan, Michael J Kahana Jan 2013

Synchronous And Asynchronous Theta And Gamma Activity During Episodic Memory Formation., John F Burke, Kareem A Zaghloul, Joshua Jacobs, Ryan B Williams, Michael R Sperling, Ashwini D Sharan, Michael J Kahana

Department of Neuroscience Faculty Papers

To test the hypothesis that neural oscillations synchronize to mediate memory encoding, we analyzed electrocorticographic recordings taken as 68 human neurosurgical patients studied and subsequently recalled lists of common words. To the extent that changes in spectral power reflect synchronous oscillations, we would expect those power changes to be accompanied by increases in phase synchrony between the region of interest and neighboring brain areas. Contrary to the hypothesized role of synchronous gamma oscillations in memory formation, we found that many key regions that showed power increases during successful memory encoding also exhibited decreases in global synchrony. Similarly, cortical theta activity …


Acute Activation, Desensitization And Smoldering Activation Of Human Acetylcholine Receptors., Barbara Campling, M.D., Frcpc, Alexander Kuryatov, Jon Lindstrom Jan 2013

Acute Activation, Desensitization And Smoldering Activation Of Human Acetylcholine Receptors., Barbara Campling, M.D., Frcpc, Alexander Kuryatov, Jon Lindstrom

Department of Neuroscience Faculty Papers

The behavioral effects of nicotine and other nicotinic agonists are mediated by AChRs in the brain. The relative contribution of acute activation versus chronic desensitization of AChRs is unknown. Sustained "smoldering activation" occurs over a range of agonist concentrations at which activated and desensitized AChRs are present in equilibrium. We used a fluorescent dye sensitive to changes in membrane potential to examine the effects of acute activation and chronic desensitization by nicotinic AChR agonists on cell lines expressing human α4β2, α3β4 and α7 AChRs. We examined the effects of acute and prolonged application of nicotine and the partial agonists varenicline, …


Degeneration Of Phrenic Motor Neurons Induces Long-Term Diaphragm Deficits Following Mid-Cervical Spinal Contusion In Mice., Charles Nicaise, Rajarshi Putatunda, Tamara J Hala, Kathleen A Regan, David M Frank, Jean-Pierre Brion, Karelle Leroy, Roland Pochet, Megan C Wright, Angelo C Lepore Dec 2012

Degeneration Of Phrenic Motor Neurons Induces Long-Term Diaphragm Deficits Following Mid-Cervical Spinal Contusion In Mice., Charles Nicaise, Rajarshi Putatunda, Tamara J Hala, Kathleen A Regan, David M Frank, Jean-Pierre Brion, Karelle Leroy, Roland Pochet, Megan C Wright, Angelo C Lepore

Department of Neuroscience Faculty Papers

A primary cause of morbidity and mortality following cervical spinal cord injury (SCI) is respiratory compromise, regardless of the level of trauma. In particular, SCI at mid-cervical regions targets degeneration of both descending bulbospinal respiratory axons and cell bodies of phrenic motor neurons, resulting in deficits in the function of the diaphragm, the primary muscle of inspiration. Contusion-type trauma to the cervical spinal cord is one of the most common forms of human SCI; however, few studies have evaluated mid-cervical contusion in animal models or characterized consequent histopathological and functional effects of degeneration of phrenic motor neuron-diaphragm circuitry. We have …


Human Glial-Restricted Progenitor Transplantation Into Cervical Spinal Cord Of The Sod1 Mouse Model Of Als., Angelo C Lepore, John O'Donnell, Andrew S Kim, Timothy Williams, Alicia Tuteja, Mahendra S Rao, Linda L Kelley, James T Campanelli, Nicholas J Maragakis Oct 2011

Human Glial-Restricted Progenitor Transplantation Into Cervical Spinal Cord Of The Sod1 Mouse Model Of Als., Angelo C Lepore, John O'Donnell, Andrew S Kim, Timothy Williams, Alicia Tuteja, Mahendra S Rao, Linda L Kelley, James T Campanelli, Nicholas J Maragakis

Department of Neuroscience Faculty Papers

Cellular abnormalities are not limited to motor neurons in amyotrophic lateral sclerosis (ALS). There are numerous observations of astrocyte dysfunction in both humans with ALS and in SOD1(G93A) rodents, a widely studied ALS model. The present study therapeutically targeted astrocyte replacement in this model via transplantation of human Glial-Restricted Progenitors (hGRPs), lineage-restricted progenitors derived from human fetal neural tissue. Our previous findings demonstrated that transplantation of rodent-derived GRPs into cervical spinal cord ventral gray matter (in order to target therapy to diaphragmatic function) resulted in therapeutic efficacy in the SOD1(G93A) rat. Those findings demonstrated the feasibility and efficacy of transplantation-based …


Slob, A Slowpoke Channel Binding Protein, Regulates Insulin Pathway Signaling And Metabolism In Drosophila., Amanda L. Sheldon, Jiaming Zhang, Hong Fei, Irwin B Levitan Aug 2011

Slob, A Slowpoke Channel Binding Protein, Regulates Insulin Pathway Signaling And Metabolism In Drosophila., Amanda L. Sheldon, Jiaming Zhang, Hong Fei, Irwin B Levitan

Department of Neuroscience Faculty Papers

There is ample evidence that ion channel modulation by accessory proteins within a macromolecular complex can regulate channel activity and thereby impact neuronal excitability. However, the downstream consequences of ion channel modulation remain largely undetermined. The Drosophila melanogaster large conductance calcium-activated potassium channel SLOWPOKE (SLO) undergoes modulation via its binding partner SLO-binding protein (SLOB). Regulation of SLO by SLOB influences the voltage dependence of SLO activation and modulates synaptic transmission. SLO and SLOB are expressed especially prominently in median neurosecretory cells (mNSCs) in the pars intercerebralis (PI) region of the brain; these cells also express and secrete Drosophila insulin like …