Physiological Processes Commons^™

The Impact Of High Intensity Interval Training On Neurogenesis And Angiogenesis In The Dentate Gyrus, Darrin Lenhart

Seton Hall University Dissertations and Theses (ETDs)

BACKGROUND: Exercise is associated with improved neuronal health and longevity, synaptic plasticity, cerebral blood volume, overall brain volume, and neurogenesis which collectively may have the power to forestall neurodegenerative disease.

PURPOSE: This study aims to explore the impact of high intensity interval training on individuals with mild cognitive impairment using a range of cognitive, physiological, and biomechanical measures. Specifically, this study seeks to assess the impact of high intensity interval training on neurogenesis and angiogenesis in the dentate gyrus of individuals with mild cognitive impairment versus healthy age-matched controls, as assessed by urinalysis of BDNF levels, performance on the Rey …

Placenta-Specific Slc38a2/Snat2 Knockdown Causes Fetal Growth Restriction In Mice, Owen R. Vaughan, Katarzyna Maksym, Elena Silva, Kenneth Barentsen, Russel V. Anthony, Sara L. Hillman, Thomas L. Brown, Rebecca Spencer, Anna L. David, Fredrick J. Rosario, Theresa L. Powell, Thomas Jansson

Neuroscience, Cell Biology & Physiology Faculty Publications

Fetal growth restriction (FGR) is a complication of pregnancy that reduces birth weight, markedly increases infant mortality and morbidity and is associated with later-life cardiometabolic disease. No specific treatment is available for FGR. Placentas of human FGR infants have low abundance of sodium-coupled neutral amino acid transporter 2 (Slc38a2/SNAT2), which supplies the fetus with amino acids required for growth. We determined the mechanistic role of placental Slc38a2/SNAT2 deficiency in the development of restricted fetal growth, hypothesizing that placenta-specific Slc38a2 knockdown causes FGR in mice. Using lentiviral transduction of blastocysts with a small hairpin RNA (shRNA), we achieved 59% knockdown of …

Intensity-Dependent Changes In Quantified Resting Cerebral Perfusion With Multiple Sessions Of Transcranial Dc Stimulation, Matthew Sherwood, Lindsey Mcintire, Aaron T. Madaris, Kamin Kim, Charan Ranganath, R. Andy Mckinley

Neuroscience, Cell Biology & Physiology Faculty Publications

Transcranial direct current stimulation (tDCS) to the left prefrontal cortex has been shown to produce broad behavioral effects including enhanced learning and vigilance. Still, the neural mechanisms underlying such effects are not fully understood. Furthermore, the neural underpinnings of repeated stimulation remain understudied. In this work, we evaluated the effects of the repetition and intensity of tDCS on cerebral perfusion [cerebral blood flow (CBF)]. A cohort of 47 subjects was randomly assigned to one of the three groups. tDCS of 1- or 2-mA was applied to the left prefrontal cortex on three consecutive days, and resting CBF was quantified before …

Current State Of Preeclampsia Mouse Models: Approaches, Relevance, And Standardization, Christopher A. Waker, Melissa R. Kaufman, Thomas L. Brown

Neuroscience, Cell Biology & Physiology Faculty Publications

Preeclampsia (PE) is a multisystemic, pregnancy-specific disorder and a leading cause of maternal and fetal death. PE is also associated with an increased risk for chronic morbidities later in life for mother and offspring. Abnormal placentation or placental function has been well-established as central to the genesis of PE; yet much remains to be determined about the factors involved in the development of this condition. Despite decades of investigation and many clinical trials, the only definitive treatment is parturition. To better understand the condition and identify potential targets preclinically, many approaches to simulate PE in mice have been developed and …

The Role Of Action Potential Waveform In Failure Of Excitation Contraction Coupling, Xueyong Wang, Murad Nawaz, Steve R.A. Burke, Roger Bannister, Brent D. Foy, Andrew A. Voss, Mark M. Rich

Neuroscience, Cell Biology & Physiology Faculty Publications

Excitation contraction coupling (ECC) is the process by which electrical excitation of muscle is converted into force generation. Depolarization of skeletal muscle resting potential contributes to failure of ECC in diseases such as periodic paralysis, ICU acquired weakness and possibly fatigue of muscle during vigorous exercise. When extracellular K+ is raised to depolarize the resting potential, failure of ECC occurs suddenly, over a range of several mV of resting potential. While some studies have hypothesized the sudden failure of ECC is due to all-or-none failure of excitation, other studies suggest failure of excitation is graded. Intracellular recordings of action potentials …

Neural Oscillatory Activity Serving Sensorimotor Control Is Regulated By The Mitochondrial Redox Environment In Health And Disease, Rachel Spooner

Theses & Dissertations

Despite effective regimens of combination antiretroviral therapy, individuals with HIV are still at higher risk for developing forms of cognitive impairment, with one of the most common behavioral abnormalities to manifest being motor dysfunction. This is an important consideration, as deficits in motor control likely contribute to higher-order cognitive impairments, which together, lead to functional dependencies in the ever-growing aging population of HIV-infected adults. While the neuroanatomical bases of motor dysfunction have recently been illuminated in people living with HIV (PLWH), there remains an open question regarding the molecular processes supporting the circuit-level neuronal dynamics that potentially serve these behavioral …

Affiliative Social Interactions Activate Vasopressin-Responsive Neurons In The Mouse Dorsal Raphe, Tirth Patel, Hanna O. Caiola, Olivia Mallari, Benjamin D. Rood

Rowan-Virtua Research Day

Social behavior is inextricably linked to human health, shaping both our susceptibility and resilience to disease and stress. Positive interactions as simple as maternal contact or friendships among children and adults can protect against emotional distress and improve treatment outcomes, whereas negative interactions such as abuse, social isolation, or bullying can increase aggression and precipitate mood disorders. Discovering the structure and function of neural circuits underlying social behavior is critical to understanding the link between social interaction and health. The neuropeptide vasopressin has been implicated in the regulation of multiple social interactions including social memory, aggression, mating, pair-bonding, and parental …

The Mechanism Underlying Transient Weakness In Myotonia Congenita, Jessica H. Myers, Kirsten Denman, Chris Dupont, Ahmed A. Hawash, Kevin R. Novak, Andrew Koesters, Manfred Grabner, Anamika Dayal, Andrew A. Voss, Mark M. Rich

Neuroscience, Cell Biology & Physiology Faculty Publications

In addition to the hallmark muscle stiffness, patients with recessive myotonia congenita (Becker disease) experience debilitating bouts of transient weakness that remain poorly understood despite years of study. We performed intracellular recordings from muscle of both genetic and pharmacologic mouse models of Becker disease to identify the mechanism underlying transient weakness. Our recordings reveal transient depolarizations (plateau potentials) of the membrane potential to -25 to -35 mV in the genetic and pharmacologic models of Becker disease. Both Na + and Ca 2+ currents contribute to plateau potentials. Na + persistent inward current (NaPIC) through Na V 1.4 channels is the …

A Mouse Model Of Huntington’S Disease Shows Altered Ultrastructure Of Transverse Tubules In Skeletal Muscle Fibers, Shannon H. Romer, Sabrina Metzger, Kristiana Peraza, Matthew C. Wright, D. Scott Jobe, Long-Sheng Song, Mark M. Rich, Brent D. Foy, Robert J. Talmadge, Andrew A. Voss

Neuroscience, Cell Biology & Physiology Faculty Publications

Huntington’s disease (HD) is a fatal and progressive condition with severe debilitating motor defects and muscle weakness. Although classically recognized as a neurodegenerative disorder, there is increasing evidence of cell autonomous toxicity in skeletal muscle. We recently demonstrated that skeletal muscle fibers from the R6/2 model mouse of HD have a decrease in specific membrane capacitance, suggesting a loss of transverse tubule (t-tubule) membrane in R6/2 muscle. A previous report also indicated that Cav1.1 current was reduced in R6/2 skeletal muscle, suggesting defects in excitation–contraction (EC) coupling. Thus, we hypothesized that a loss and/or disruption of the skeletal muscle t-tubule …

Neurophysiology Of Space Medicine: A Literature Review, Jose R. Velasquez

MEDI 9331 Scholarly Activities Clinical Years

Space medicine is becoming an essential and expanding clinical discipline. Acquiring a deeper and complete picture understanding of the multi-systemic response due to space on human health and function is essential to ensure the success of future space exploration. A comprehensive review of the literature was performed using PubMed and focused on the current neurophysiologic findings of the central nervous system’s response to space. Ground-based analogues, which mimic the effects of microgravity, and actual spaceflight studies have been used to analyze these physiologic adaptations to space. Overall, cerebellar, sensorimotor and vestibular brain regions seem to be affected the most. Through …

The Role Of Microtubule-Associated Protein Tau In Neuronal Excitability And Epileptogenesis, Ryan A. Cloyd

Theses and Dissertations--Physiology

Tauopathies, including Alzheimer’s disease (AD), are devastating diseases with an immense burden on society which is predicted to increase in coming decades. In addition to progressive loss of memory and cognitive function, patients with tauopathies have a 6-10 fold increase in lifetime risk for seizures, and many are diagnosed with epilepsy. The presence of epileptiform activity on electroencephalogram (EEG) recordings from patients with AD predicts faster cognitive decline compared to patients without abnormal EEG readings. Electrophysiological measurements in murine models of AD have identified neuronal hyperexcitability. Furthermore, reducing tau phosphorylation or expression confers seizure resistance in animal epilepsy models. Although …

Mental Health & Drugs; A Map Of The Mind, Wylie Jones Jordan

Journal of Mind and Medical Sciences

The practice of physical medicine underwent a sea change at the turn of the 20th century, but the management of mental disorders stayed much the same as it had been since Rome. New names have been coined for disorders, and synthetic drugs are advertised as a solution to every problem, but the causes are still largely unknown and, although spontaneous remission can occur, there are no cures. This review of psychiatric diagnosis and treatment from Rome to the 21st century offers a rationale to support the classic (and still current) classification of disorders. It offers a method of distinguishing the …

Effects Of Neuronic Shutter Observed In The Eeg Alpha Rhythm, Kevin E. Alexander, Justin R. Estepp, Sherif M. Elbasiouny

Neuroscience, Cell Biology & Physiology Faculty Publications

The posterior alpha (α) rhythm, seen in human electroencephalogram (EEG), is posited to originate from cycling inhibitory/excitatory states of visual relay cells in the thalamus. These cycling states are thought to lead to oscillating visual sensitivity levels termed the “neuronic shutter effect.” If true, perceptual performance should be predictable by observed α phase (of cycling inhibitory/excitatory states) relative to the timeline of afferentiation onto the visual cortex. Here, we tested this hypothesis by presenting contrast changes at near perceptual threshold intensity through closed eyelids to 20 participants (balanced for gender) during times of spontaneous α oscillations. To more accurately and …

Conditional Loss Of Engrailed 1/2 In Rhombic Lip-Derived Neurons Increases Intrinsic Rhythmicity And Decreases Overall Variability Of Eupneic Respiration, Angela P. Taylor

Theses and Dissertations (ETD)

Evidence for a cerebellar role during cardiopulmonary challenges has long been established, but investigation into cerebellar involvement in eupneic breathing has been inconclusive. Given the view of the cerebellum (CRB) as a temporally coordinating structure, any investigation into the CRB during respiration must evaluate rhythm and variability of the respiratory sequence. In this study, we chose an elegant model of cerebellar neuropathology, Atoh1-En1/2 CKO, where mutant animals have conditional loss of the developmental patterning gene Engrailed 1/2 in rhombic lip-lineage neurons and exhibit a proportional scaling-down of neuron number in hypoplastic lobules of the CRB. We utilized whole-body unrestrained plethysmography …

Genomic Instability And The Oncohistone H3k27m Drive Gliomagenesis In A Murine Model, Lee J. Pribyl

Theses and Dissertations (ETD)

Maintaining genome stability is crucial for human health and it is of particular importance in neural cells during early brain development. Genome maintenance occurs at two broad stages; surveillance during DNA replication and DNA damage repair in differentiating and mature cells. Neural cells are particularly sensitive to DNA strand breaks and defective DNA damage responses can result in detrimental effects on the nervous system, including cancer. Multiple DNA repair pathways play critical roles in preventing DNA damage accumulation in stem and neural progenitor cells. The mechanisms that protect progenitor genomes also suppress DNA mutations that can result in cancer. A …

Multiquantal Glutamate Release From Rod Photoreceptors, Cassandra L. Hays

Theses & Dissertations

Neurons communicate via Ca²⁺-dependent release of neurotransmitters packaged into vesicles (quanta). Some CNS neurons, especially sensory synapses, can release multiple vesicles at a time, increasing information transmission and overcoming the unreliability of a stochastic process. Ribbon-bearing neurons, including retinal photoreceptors, face the challenge of encoding sensory receptor potentials into an ever-changing train of vesicle release events. We studied release of glutamate using voltage clamp to measure anion currents activated during glutamate reuptake into presynaptic terminals (I_A(glu)) of salamander and mouse rods, finding that each employ distinct mechanisms for multiquantal release. In amphibian rods, we found that …

Depressed Neuromuscular Transmission Causes Weakness In Mice Lacking Bk Potassium Channels, Xueyong Wang, Steven R.A. Burke, Robert J. Talmadge, Andrew A. Voss, Mark M. Rich

Neuroscience, Cell Biology & Physiology Faculty Publications

Mice lacking functional large-conductance voltage- and Ca2+-activated K+ channels (BK channels) are viable but have motor deficits including ataxia and weakness. The cause of weakness is unknown. In this study, we discovered, in vivo, that skeletal muscle in mice lacking BK channels (BK−/−) was weak in response to nerve stimulation but not to direct muscle stimulation, suggesting a failure of neuromuscular transmission. Voltage-clamp studies of the BK−/− neuromuscular junction (NMJ) revealed a reduction in evoked endplate current amplitude and the frequency of spontaneous vesicle release compared with WT littermates. Responses to 50-Hz stimulation indicated a reduced probability of vesicle release …

Covid 19 What You Need To Know, Dawn P. Wooley, Giancarlo Mariani, Craig Woolley, Laura M. Luehrmann

Neuroscience, Cell Biology & Physiology Faculty Publications

This is the first presentation in the new Shelter-in-Place lecture series. This first lecture is two-fold. First, it covers the basics of the COVID-19 virus including: how it spreads, possible origin, and other pertinent information. This portion of the presentation was followed by an overview of the international recruitment efforts in response to the virus, including: student perspectives, recruitment methods, and other important information.

Sciatic Nerve Cut And Repair Using Fibrin Glue In Adult Mice, Erica T. Akhter, Travis M. Rotterman, Arthur W. English, Francisco J. Alvarez

Neuroscience, Cell Biology & Physiology Faculty Publications

Peripheral nerve injury (PNI) is an excellent model for studying neural responses to injury and elucidating the mechanisms that can facilitate axon regeneration. As such, several animal models have been employed to study regenerative mechanisms after PNI, including Aplysia, zebrafish, rabbits, cats and rodents. This protocol describes how to perform a sciatic nerve injury and repair in mice, one of the most frequently used models to study mechanisms that facilitate recovery after PNI, and that takes advantage of the availability of many genetic models. In this protocol, we describe a method for using fibrin glue to secure the proximal …

Self-Directed Down-Regulation Of Auditory Cortex Activity Mediated By Real-Time Fmri Neurofeedback Augments Attentional Processes, Resting Cerebral Perfusion, And Auditory Activation, Matthew Sherwood, Jason G. Parker, Emily E. Diller, Subhashini Ganapathy, Kevin B. Bennett, Carlos R. Esquivel, Jeremy T. Nelson

Neuroscience, Cell Biology & Physiology Faculty Publications

In this work, we investigated the use of real-time functional magnetic resonance imaging (fMRI) with neurofeedback training (NFT) to teach volitional down-regulation of the auditory cortex (AC) using directed attention strategies as there is a growing interest in the application of fMRI-NFT to treat neurologic disorders. Healthy participants were separated into two groups: the experimental group received real feedback regarding activity in the AC; the control group was supplied sham feedback yoked from a random participant in the experimental group and matched for fMRI-NFT experience. Each participant underwent five fMRI-NFT sessions. Each session contained 2 neurofeedback runs where participants completed …

Initial Characterization Of The Indole-3-Carboxamide Bic-154 As A Fast Onset And Reversible Orai Channel Blocker, Tetyana Zhelay, Kalina Szteyn, Elisa Liardo, Jae Eun Cheong, Steffi Koerner, Anil Ekkati, Lijun Sun, J. Ashot Kozak

Neuroscience, Cell Biology & Physiology Faculty Publications

Calcium ion elevations are required for human T-lymphocyte proliferation in response to antigen recognition by a T-cell receptor. Calcium influx through the plasma membrane is necessary for efficient T-cell proliferation and effector function. The calcium channels responsible for Ca2+ influx in lymphocytes have been identified and Orai interacting with ER Ca2+ sensor STIM were shown to be crucial for persistent calcium mobilization. Loss-of-function mutations in Orai1 or STIM1 result in severe combined immunodeficiency (SCID) with muscle hypotonia. Suppression of calcium influx through Orai/STIM channels gives rise to various lymphoproliferative defects. Thus, deletion of Orai or STIM in mice results in …

Repetitive Transcranial Electrical Stimulation Induces Quantified Changes In Resting Cerebral Perfusion Measured From Arterial Spin Labeling, Matthew Sherwood, Aaron T. Madaris, Casserly R. Mullenger, R. Andy Mckinley

Neuroscience, Cell Biology & Physiology Faculty Publications

The use of transcranial electrical stimulation (TES) as a method to augment neural activity has increased in popularity in the last decade and a half. The specific application of TES to the left prefrontal cortex has been shown to produce broad cognitive effects; however, the neural mechanisms underlying these effects remain unknown. In this work, we evaluated the effect of repetitive TES on cerebral perfusion. Stimulation was applied to the left prefrontal cortex on three consecutive days, and resting cerebral perfusion was quantified before and after stimulation using arterial spin labeling. Perfusion was found to decrease significantly more in a …

Neuroprotective Functions Of Docosahexaenoic Acid And Epidermal Fatty Acid Binding Protein, Manuel Luis Montero

Loma Linda University Electronic Theses, Dissertations & Projects

Lipotoxicity (LTx) is involved in mostly every process of neuronal injury. Using NGFDPC12 cells we show that palmitic acid (PA) induces the expression of stress response genes HIF-1α and BNIP3, increases the accumulation of reactive oxygen species, and decreases cell viability by apoptosis. Inhibition of cathepsins does not rescue neurons from PA-LTx but inhibition of necroptosis and promotion of autophagy do. DHA decreases the expression of HIF-1α and BNIP3 and rescues PA-induced cell death by inhibiting apoptosis and necroptosis. Besides DHA stimulates the mRNA expression, phosphorylation and conjugation of autophagy controlling proteins. Inhibiting autophagy during DHA treatment decreases its capacity …

Gender- And Region-Specific Changes In Estrogen Signaling In Aging Rat Brain Mitochondria, Christopher M. Evola, Tanner L. Hudson, Luping Huang, Adrian M. Corbett, Debra A. Mayes

Neuroscience, Cell Biology & Physiology Faculty Publications

Recently epidemiological studies suggest females lose neuroprotection from neurodegenerative diseases as they go through menopause. It has been hypothesized that this neuroprotection is hormone‐dependent. The current study characterized cell signaling molecules downstream of estrogen receptor beta that are known to play a role in memory, PKC, ERK, and connexin‐43, in regions of the brain associated with memory decline in an attempt to elucidate significant changes that occur post‐estrus. Total whole cell lysates were compared to isolated mitochondrial protein because mitochondrial function is known to be altered during aging. As hypothesized, protein concentrations differed depending on age, gender, and brain region. …

Volitional Down-Regulation Of The Primary Auditory Cortex Via Directed Attention Mediated By Real-Time Fmri Neurofeedback, Matthew Sherwood, Jason G. Parker, Emily E. Diller, Subhashini Ganapathy, Kevin B. Bennett, Jeremy T. Nelson

Neuroscience, Cell Biology & Physiology Faculty Publications

The present work assessed the efficacy of training volitional down-regulation of the primary auditory cortex (A1) based on real-time functional magnetic resonance imaging neurofeedback (fMRI-NFT). A1 has been shown to be hyperactive in chronic tinnitus patients, and has been implicated as a potential source for the tinnitus percept. 27 healthy volunteers with normal hearing underwent 5 fMRI-NFT sessions: 18 received real neurofeedback and 9 sham neurofeedback. Each session was composed of a simple auditory fMRI followed by 2 runs of A1 fMRI-NFT. The auditory fMRI alternated periods of no auditory with periods of white noise stimulation at 90 dB. A1 …

Thalamocortical Processing Of Temporal Cues In Sounds, Kasey Smith

Honors Scholar Theses

The ability of the brain to extract meaningful information from complex sounds is what allows mammals to understand species-specific communication as well as important environmental cues such as the sound of water or of potential predators or prey. The auditory cortex of humans and other mammals contains multiple cortical regions that unique sensitivities to both spectral and temporal sound cues. This discourse will explore three main factors proposed to determine these distinct processing capabilities in regard to temporal sound cues; the distribution of glutamate transporters in the thalamus, the architecture of afferent pathways between the thalamus and auditory cortex, and …

Single Session Low Frequency Left Dorsolateral Prefrontal Transcranial Magnetic Stimulation Changes Neurometabolite Relationships In Healthy Humans, Matthew Sherwood, Richard A. Mckinley, Danielle Boeke, Jason G. Parrker, Lindsey K. Mcintire, Justin M. Nelson, Catherine Fletchall, Natasha Alexander, Amanda Mcconnell, Chuck Goodyear, Jeremy T. Nelson, Nathaniel R. Bridges

Neuroscience, Cell Biology & Physiology Faculty Publications

Background: Dorsolateral prefrontal cortex (DLPFC) low frequency repetitive transcranial magnetic stimulation (LF-rTMS) has shown promise as a treatment and investigative tool in the medical and research communities. Researchers have made significant progress elucidating DLPFC LF-rTMS effects—primarily in individuals with psychiatric disorders. However, more efforts investigating underlying molecular changes and establishing links to functional and behavioral outcomes in healthy humans are needed. Objective: We aimed to quantify neuromolecular changes and relate these to functional changes following a single session of DLPFC LF-rTMS in healthy participants. Methods: Eleven participants received sham-controlled neuronavigated 1 Hz rTMS to the region most activated by a …

Muscle Nicotinic Acetylcholine Receptors May Mediate Trans-Synaptic Signaling At The Mouse Neuromuscular Junction, Xueyong Wang, J. Michael Mcintosh, Mark M. Rich

Neuroscience, Cell Biology & Physiology Faculty Publications

Block of neurotransmitter receptors at the neuromuscular junction (NMJ) has been shown to trigger upregulation of the number of synaptic vesicles released (quantal content, QC), a response termed homeostatic synaptic plasticity. The mechanism underlying this plasticity is not known. Here, we used selective toxins to demonstrate that block of α1-containing nicotinic acetylcholine receptors (nAChRs) at the NMJ of male and female mice triggers the upregulation of QC. Reduction of current flow through nAChRs, induced by drugs with antagonist activity, demonstrated that reduction in synaptic current per se does not trigger upregulation of QC. These data led to the remarkable conclusion …

Trpm7 Current Inactivation: Evidence For Inside-Out Signaling, Tetyana Zhelay, J. Ashot Kozak

Neuroscience, Cell Biology & Physiology Faculty Publications

TRPM7 channels conduct metal cations such as Na+, K+, Ca2+ and Mg2+. In the presence of external Ca2+/Mg2+ TRPM7 has a steeply outwardly rectifying current-voltage (I-V) relation. In the absence of Ca2+/Mg2+ the IV becomes semi-linear. This has been explained by the removal of pore blockade by divalent cations (e.g. Ca2+o/Mg2+o). TRPM7 channels are inhibited by cytoplasmic Mg2+ in a voltage-independent manner, primarily by a reversible reduction in the overall number of conducting channels. Here, we have examined the consequences of external Ca2+ removal and reintroduction on TRPM7 current kinetics. In whole-cell patch clamp with low internal Mg2+, we rapidly …

Inactivation Of Trpm7 Kinase In Mice Results In Enlarged Spleens, Reduced T-Cell Proliferation And Diminished Store-Operated Calcium Entry, Pavani Beesetty, Krystyna Blanka Wieczerzak, Jennifer Gibson, Taku Kaitsuka, Charles Tuan Luu, Masayuki Matsushita, J. Ashot Kozak

Neuroscience, Cell Biology & Physiology Faculty Publications

T lymphocytes enlarge (blast) and proliferate in response to antigens in a multistep program that involves obligatory cytosolic calcium elevations. Store-operated calcium entry (SOCE) pathway is the primary source of Ca2+ in these cells. Here, we describe a novel modulator of blastogenesis, proliferation and SOCE: the TRPM7 channel kinase. TRPM7 kinase-dead (KD) K1646R knock-in mice exhibited splenomegaly and impaired blastogenic responses elicited by PMA/ionomycin or anti-CD3/CD28 antibodies. Splenic T-cell proliferation in vitro was weaker in the mutant compared to wildtype littermates. TRPM7 current magnitudes in WT and KD mouse T cells were, however, similar. We tested the dependence of T-cell …