Sleep is an essential process conserved from flies to humans. The importance of sleep underscored by its tight homeostatic control. Through a forward genetic screen, we identified gene, sleepless, required for in Drosophila. sleepless gene encodes brain-enriched, glycosylphosphatidylinositol-anchored protein. Loss SLEEPLESS protein caused extreme (>80%) reduction sleep; moderate had minimal effects on baseline but markedly reduced the amount recovery after deprivation. Genetic and molecular...

The gene for hSK4, a novel human small conductance calcium-activated potassium channel, or SK has been identified and expressed in Chinese hamster ovary cells. In physiological saline hSK4 generates of approximately 12 pS, value close agreement with that other cloned channels. Like members this family, the polypeptide encoded by contains previously unnoted leucine zipper-like domain its C terminus unknown function. appears unique, however, very high affinity Ca2+ (EC50 95 nM) predominant...

Neuronal stressors such as hypoxia and firing of action potentials at very high frequencies cause intracellular Na+ to rise ATP be consumed faster than it can regenerated. We report the cloning a gene encoding K+ channel, Slick, demonstrate that functionally is hybrid between two classes channels, Na+-activated (KNa) ATP-sensitive (KATP) channels. The Slick channel activated by Cl- inhibited ATP. widely expressed in CNS detected heart. identify consensus binding site near C terminus required...

Human T lymphocytes express a Ca²⁺-activated K⁺ current (IK), whose roles and regulation are poorly understood. We amplified hSK4 cDNA from human lymphoblasts, we showed that its biophysical pharmacological properties when stably expressed in Chinese hamster ovary cells were essentially identical to the native IK current. In activated mRNA increased 14.6-fold (Kv1.3 1.3-fold), with functional consequences. Proliferation was inhibited Kv1.3 blocked naive cells, but block...

One major unanswered question in neuroscience is how the brain transitions between conscious and unconscious states. General anesthetics offer a controllable means to study these transitions. Induction of anesthesia commonly attributed drug-induced global modulation neuronal function, while emergence from has been thought occur passively, paralleling elimination anesthetic its sites central nervous system (CNS). If this were true, then CNS concentrations on induction would be...

The needs fulfilled by sleep are unknown, though the effects of insufficient manifold. To better understand how need to is sensed and discharged, much effort has gone into identifying neural circuits involved in regulating arousal, especially those that promote sleep. In prevailing models, dorsal fan-shaped body (dFB) plays a central role this process fly brain. present study we manipulated various properties dFB including its electrical activity, synaptic output, endogenous gene expression....

The question is, does the isoform hSK4, also designated KCNN4, represent small conductance, Ca 2 + -activated K channel (Gardos channel) in human red blood cells? We have analyzed reticulocyte RNA by RT-PCR, and, of four isoforms SK channels known, only SK4 was found. Northern blot analysis purified and synchronously growing erythroid progenitor cells, differentiating from erythroblasts to reticulocytes, again showed presence SK4. Western analysis, with an anti-SK4 antibody, that cells...

In order to characterize the genetic mechanisms underlying sleep, we have carried out a large-scale screen in Drosophila identify short-sleeping mutants. The objectives of this study were as follows: (1) phenotypes shortest-sleeping mutants; (2) examine whether changes arousal threshold or sleep homeostasis underlie phenotypes; (3) clone gene affected one shortest sleepers; and (4) investigate circadian mutants can be identified using light:dark (L:D) locomotor data obtained for studying...

Obesity has dramatically increased in prevalence, making it essential to understand its accompanying metabolic changes. Modeling diet-induced obesity Drosophila melanogaster (fruit flies), we elucidated transcriptional and changes w (1118) flies on a high-fat diet (HFD). Mass spectrometry-based metabolomics revealed altered fatty acid, amino carbohydrate metabolism with HFD. Microarray analysis uncovered nitrogen metabolism, including CG9510, homolog of human argininosuccinate lyase (ASL)....

Traumatic brain injury (TBI) is a major cause of morbidity and mortality worldwide. In addition, there has been growing appreciation that even repetitive, milder forms TBI (mTBI) can have long-term deleterious consequences to neural tissues. Hampering our understanding genetic environmental factors influence the cellular molecular responses limited availability effective model systems could be used identify key genes pathways modulate both acute TBI. Here we report development severe...

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

Abstract It has been postulated that synaptic potentiation during waking is offset by a homoeostatic reduction in net strength sleep. However, molecular mechanisms to support such process are lacking. Here we demonstrate deficiencies the RNA-editing gene Adar increase sleep due dysfunction glutamatergic neurons Drosophila . Specifically, vesicular glutamate transporter upregulated, leading over-activation of NMDA receptors, and reserve pool vesicles selectively expanded mutants. Collectively...

Calmodulin (CaM) regulates gating of several types ion channels but has not been implicated in channel assembly or trafficking. For the SK4/IK1 K+ channel, CaM bound to proximal C terminus ("Ct1 " domain) acts as Ca2+ sensor. We now show that interacting with SK4 also controls and surface expression. In transfected cells, removing free by overexpressing CaM-binding domain, Ct1, redistributed full-length protein from plasma membrane cytoplasm decreased whole-cell currents. Making more...

α7 nAChRs are expressed widely throughout the brain, where they important for synaptic signaling, gene transcription, and plastic changes that regulate sensory processing, cognition, neural responses to chronic nicotine exposure. However, mechanisms by which regulated poorly understood. Here we show trafficking of α7-subunits is controlled endogenous membrane-associated prototoxins in Ly6 family. In particular, find Ly6h reduces cell-surface expression calcium signaling nAChRs. We detect...

α4β2 nicotinic acetylcholine receptors (nAChRs) are abundantly expressed throughout the central nervous system and thought to be primary target of nicotine, main addictive substance in cigarette smoking. Understanding mechanisms by which these regulated may assist developing compounds selectively interfere with nicotine addiction. Here we report previously unrecognized modulatory properties members Ly6 protein family on nAChRs. Using a FRET-based Ca(2+) flux assay, found that maximum...