A Method for High Fidelity Optogenetic Control of Individual Pyramidal Neurons <em>In vivo</em>

Optogenetic methods  have emerged as a powerful tool for elucidating neural circuit activity  underlying a diverse set of behaviors across a broad range ...

University of Colorado Boulder

Exposure to uncontrollable stressors produces a variety of behavioral consequences (e.g. exaggerated fear, reduced social exploration) that do not occur if the stressor is controllable. In addition, an initial experience with a controllable stressor can block the behavioral and neural responses to a later uncontrollable stressor. The serotonergic (5-HT) dorsal raphe nucleus (DRN) has come to be viewed as a critical structure in mediating the behavioral effects of uncontrollable stress. Recent work suggests that the buffering effects of behavioral control on the DRN-dependent behavioral outcomes of uncontrollable stress require ventral medial prefrontal cortex (mPFCv) activation at the time of behavioral control. The present studies were conducted to directly determine whether or not controllable stress selectively activates DRN-projecting neurons within the mPFCv. To examine this possibility in the rat, we combined retrograde tracing (fluorogold iontophoresed into the DRN) with Fos immunohistochemistry, a marker for neural activation. Exposure to controllable, relative to uncontrollable, stress increased Fos expression in fluorogold-labeled neurons in the prelimbic region (PL) of the mPFCv. Furthermore, in a separate experiment, a prior experience with controllable stress led to potentiation of Fos expression in retrogradely labeled PL neurons in response to an uncontrollable stressor 1 week later. These results suggest that the PL selectively responds to behavioral control and utilizes such information to regulate the brainstem response to ongoing and subsequent stressors.

Selective activation of dorsal raphe nucleus-projecting neurons in the ventral medial prefrontal cortex by controllable stress.

Cognitive impairments influence alcohol and drug treatment outcomes, though little is known about how neurocognition affects the development of harmful substance use patterns. This study examined the influence of adolescent attention functioning on the development of substance use problems in 66 high-risk youths over an 8-year period.

Attention dysfunction predicts substance involvement in community youths.

The selective loss of somatostatin (SST)-containing interneurons from the hilus of the dentate gyrus is a hallmark of epileptic hippocampus. The functional consequence of this loss, including its contribution to postseizure hyperexcitability, remains unclear. We address this issue by characterizing the actions of SST in mouse dentate gyrus using electrophysiological techniques. Although the majority of dentate SST receptors are located in the outer molecular layer adjacent to lateral perforant path (LPP) synapses, we found no consistent action of SST on standard synaptic responses generated at these synapses. However, when SST was present during application of high-frequency trains that normally generate long-term potentiation (LTP), the induction of LTP was impaired. SST did not alter the maintenance of LTP when applied after its induction. To examine the mechanism by which SST inhibits LTP, we recorded from dentate granule cells and examined the actions of this neuropeptide on synaptic transmission and postsynaptic currents. Unlike findings in the CA1 hippocampus, we observed no postsynaptic actions on K(+) currents. Instead, SST inhibited Ca(2+)/Ba(2+) spikes evoked by depolarization. This inhibition was dependent on N-type Ca(2+)currents. Blocking these currents also blocked LTP, suggesting a mechanism through which SST may inhibit LTP. Our results indicate that SST reduction of dendritic Ca(2+) through N-type Ca(2+) channels may contribute to modulation of synaptic plasticity at LPP synapses. Therefore the loss of SST function postseizure could result in abnormal synaptic potentiation that contributes to epileptogenesis.

Somatostatin depresses long-term potentiation and Ca2+ signaling in mouse dentate gyrus.

Cue reactivity in alcohol dependent adults has revealed autonomic, cognitive, and neural responses to alcohol-related stimuli that differ from those of nonabusers. Cue reactivity and craving responses have not been studied in youth.

fMRI BOLD response to alcohol stimuli in alcohol dependent young women.

Cortistatin-14 (CST) is a neuropeptide expressed in cortical and hippocampal interneurons that shares 11 of 14 residues with somatostatin. In contrast to somatostatin, infusion of CST decreases locomotor activity and selectively enhances slow wave sleep. Here, we show that transgenic mice that overexpress cortistatin under the control of neuron-specific enolase promoter do not express long-term potentiation in the dentate gyrus. This blockade of dentate LTP correlates with profound impairment of hippocampal-dependent spatial learning. Exogenously applied CST to slices of wild-type mice also blocked induction of LTP in the dentate gyrus. Our findings implicate cortistatin in the modulation of synaptic plasticity and cognitive function. Thus, increases in hippocampal cortistatin expression during aging could have an impact on age-related cognitive deficits.

Cortistatin overexpression in transgenic mice produces deficits in synaptic plasticity and learning.

Prior exposure to a stressor can potentiate CNS pro-inflammatory immune responses to a peripheral immune challenge. However, the neuroimmune substrate(s) mediating this effect has not been determined. The present investigation examined whether microglia serve as this neuroimmune substrate given that microglia are the primary immune effector cell in the CNS. The effect of inescapable shock (IS) on glial activation (MHC II, CD11b, Iba-1, and GFAP) and regulatory markers (CD200) in vivo, and microglia pro-inflammatory responses (interleukin-1beta; IL-1beta) to lipopolysaccharide (LPS) ex vivo, were assessed in rat hippocampus. IS upregulated the microglia activation marker MHC II 24h post-IS, while the astroglia marker GFAP was unaffected. IS also downregulated the neuronal glycoprotein CD200, which functions to hold microglia in a quiescent state. Moreover, IS potentiated the pro-inflammatory response to LPS ex vivo 24h post-IS in isolated hippocampal microglia. Finally, the behavioral controllability of shock was manipulated and the effect of escapable (controllable) shock was comparable to the effect of IS on hippocampal microglia responses to LPS ex vivo. The present results suggest that stress can activate microglia, thereby sensitizing the pro-inflammatory reactivity of microglia to immunogenic stimuli.

Microglia serve as a neuroimmune substrate for stress-induced potentiation of CNS pro-inflammatory cytokine responses.

The degree of control that an organism has over a stressor potently modulates the impact of the stressor, with uncontrollable stressors producing a constellation of outcomes that do not occur if the stressor is behaviorally controllable. It has generally been assumed that this occurs because uncontrollability actively potentiates the effects of stressors. Here it will be suggested that in addition, or instead, the presence of control actively inhibits the impact of stressors. At least in part, this occurs because (i) the presence of control is detected by regions of the ventral medial prefrontal cortex (mPFCv); and (ii) detection of control activates mPFCv output to stress-responsive brain stem and limbic structures that actively inhibit stress-induced activation of these structures. Furthermore, an initial experience with control over stress alters the mPFCv response to subsequent stressors so that mPFCv output is activated even if the subsequent stressor is uncontrollable, thereby making the organism resilient. The general implications of these results for understanding resilience in the face of adversity are discussed.

Behavioral control, the medial prefrontal cortex, and resilience.

A prior experience of behavioral control over a stressor interferes with subsequent Pavlovian fear conditioning, and this effect is dependent on the activation of the ventral medial prefrontal cortex (mPFCv) at the time of the initial experience with control. It is unknown whether mPFCv activity is necessary during fear learning and/or testing for this interference to occur. One week following controllable stress, the infralimbic cortex (IL) was temporarily inactivated either before fear learning or later testing. Inactivation of the IL before the test for conditioned fear, but not before conditioning, blocked the fear reducing effects of prior controllable stress. This suggests that the experience with control interferes with the expression of fear behavior and not the learning of the association, and that the mPFCv is needed to regulate conditioned fear behavior.

Role of the ventral medial prefrontal cortex in mediating behavioral control-induced reduction of later conditioned fear.

Safety signals are learned cues that predict stress-free periods whereas behavioral control is the ability to modify a stressor by behavioral actions. Both serve to attenuate the effects of stressors such as uncontrollable shocks. Internal and external cues produced by a controlling behavior are followed by a stressor-free interval, and so it is possible that safety learning is fundamental to the effect of control. If this is the case then behavioral control and safety should recruit the same neural machinery. Interestingly, safety signals that prevented a behavioral outcome of stressor exposure that is also blocked by control (reduced social exploration) failed to inhibit activity in the dorsal raphÃ© nucleus or use the ventromedial prefrontal cortex, the mechanisms by which behavioral control operates. However, bilateral lesions to a region of posterior insular cortex, termed the "sensory insula," prevented the effect of safety but not of behavioral control, providing a double-dissociation. These results indicate that stressor-modulators can recruit distinct neural circuitry and imply a critical role of the sensory insula in safety learning.

The sensory insular cortex mediates the stress-buffering effects of safety signals but not behavioral control.

An important factor in determining the adverse consequences of a stress experience is the degree to which an individual can exert control over the stressor. Stressor controllability is known to influence brain norepinephrine levels, but its impact on activity in noradrenergic cell bodies is unknown. In the present study we investigated whether noradrenergic neurons within the locus coeruleus (LC), the major source of forebrain norepinephrine, are sensitive to stressor controllability. We exposed adult male Sprague-Dawley rats to escapable or yoked inescapable tailshock and assessed LC activity by measuring changes in the immediate early gene c-fos and the enzyme tyrosine hydroxylase (TH). We used in situ hybridization to measure levels of c-fos mRNA, TH mRNA, and TH primary transcript in the LC. In all three cases stress exposure increased expression relative to an unstressed homecage control group, but expression did not differ between controllable and uncontrollable stress. To further examine whether stressor controllability influences the number of stress-responsive LC neurons we performed double-label immunohistochemistry for TH and Fos. Again we detected an overall effect of stress, which did not differ between controllable and uncontrollable stress. We conclude that exposure to stress robustly increases expression of TH and c-fos in the LC, but this effect is not influenced by stressor controllability. To the extent that the expression of these genes reflects degree of neuronal activation, our results suggest that stress-induced activity of noradrenergic cell bodies in the LC is not sensitive to stressor controllability.

Stress-induced activity in the locus coeruleus is not sensitive to stressor controllability.

Activation of the infralimbic region (IL) of the medial prefrontal cortex (mPFC) reduces conditioned fear in a variety of situations, and the IL is thought to play an important role in the extinction of conditioned fear. Here we report a series of experiments using contextual fear conditioning in which the IL is activated with the GABAa antagonist picrotoxin (Ptx) during a single extinction session in the fear context. We investigate the impact of this manipulation on subsequent extinction sessions in which Ptx is no longer present. First, we demonstrate that a single treatment with intra-IL Ptx administered in a conditioned fear context greatly accelerates the rate of extinction on the following days. Importantly, IL-Ptx also enhances extinction to a different fear context than the one in which IL-Ptx was administered. Thus, IL-Ptx primes extinction learning regardless of the fear context in which the IL was initially activated. Second, activation of the IL must occur in conjunction with a fear context in order to enhance extinction; the extinction enhancing effect is not observable if IL-Ptx is administered in a neutral context. Finally, this extinction enhancing effect is specific to the IL for it does not occur if Ptx is injected into the prelimbic region (PL) of the mPFC. The results indicate a novel persisting control of fear induced by activation of the IL and suggest that IL activation induces changes in extinction-related circuitry that prime extinction learning.

Activation of the infralimbic cortex in a fear context enhances extinction learning.

&#x6C89;&#x9ED8;&#x57FA;&#x56E0;&#x6709;&#x9488;&#x5BF9;&#x6027;&#x7684;&#x795E;&#x7ECF;&#x5143;&#x5728;&#x5927;&#x8111;&#x4E2D;&#x7684;&#x7535;&#x6D3B;&#x52A8;&#x7684;&#x6280;&#x672F;&#x662F;&#x91CD;&#x8981;&#x7684;&#x8BC4;&#x4F30;&#x7279;&#x5B9A;&#x7684;&#x5355;&#x5143;&#x683C;&#x7C7B;&#x578B;&#x548C;&#x9014;&#x5F84;&#x5BF9;&#x884C;&#x4E3A;&#x548C;&#x75C5;&#x75C7;&#x7684;&#x8D21;&#x732E;&#x3002;&#x6700;&#x8FD1;&#x6211;&#x4EEC;&#x53D1;&#x73B0;&#x4ECE; Halorubrum sodomense (&#x62F1;) archaerhodopsin 3&#x3001; &#x5149;&#x9A71;&#x52A8;&#x5916;&#x5411;&#x8D28;&#x5B50;&#x6CF5;&#xFF0C;&#x5F53;&#x57FA;&#x56E0;&#x8868;&#x8FBE;&#x795E;&#x7ECF;&#x5143;&#xFF0C;&#x4F7F;&#x4ED6;&#x4EEC;&#x80FD;&#x591F;&#x54CD;&#x5E94;&#x7684;&#x5149;&#x8109;&#x51B2;&#x6709;&#x529B;&#x3001; &#x6682;&#x6001;&#xFF0C;&#x5E76;&#x4E00;&#x518D;&#x6C89;&#x9ED8;&#x3002;&#x7531;&#x4E8E;&#x62F1;&#x4EE4;&#x4EBA;&#x5370;&#x8C61;&#x6DF1;&#x523B;&#x7684;&#x7279;&#x70B9;&#xFF0C;&#x6211;&#x4EEC;&#x63A2;&#x8BA8;&#x7684;&#x9057;&#x4F20;&#x5B66;&#x7684;&#x7EFF;&#x5149;&#x66F4;&#x9AD8;&#x7684;&#x5E8F;&#x5217;&#x540C;&#x6E90;&#x6027;&#x4E0E;&#x5B9E;&#x7528;&#x7A0B;&#x5E8F;&#x62F1;&#xFF0C;&#x4ECE;&#x53E4; Halorubrum &#x5C5E;&#x7684;&#x7EC6;&#x83CC;&#x3002;&#x6211;&#x4EEC;&#x53D1;&#x73B0; archaerhodopsin Halorubrum &#x5E94;&#x53D8; TP009&#xFF0C;&#x4ECE;&#x6211;&#x4EEC;&#x88AB;&#x547D;&#x540D;&#x4E3A; ArchT&#xFF0C;&#x53EF;&#x4EE5;&#x8C03;&#x89E3;&#x7684;&#x62F1; (&#x4F53;&#x5916; &sim;900 pA)&#xFF0C;&#x4F46;&#x4E0E;&#x7C7B;&#x4F3C;&#x6700;&#x5927;&#x632F;&#x5E45; photocurrents &gt; &#x5149;&#x654F;&#x611F;&#x5EA6;&#x4E0A;&#x62F1;&#xFF0C;&#x6700;&#x5F15;&#x4EBA;&#x6CE8;&#x76EE;&#x7684;&#x662F;&#x9057;&#x4F20;&#x5B66;&#x8303;&#x56F4;&#x5185;&#x7684; 1 10 mW/mm(2)&#xFF0C;&#x76F8;&#x7B49;&#x4E8E;&#x4E09;&#x6298;&#x6539;&#x5584; &gt; 2 &times; &#x5904;&#x7406;&#x7684;&#x5178;&#x578B;&#x7684;&#x5355;&#x5149;&#x7EA4;&#x7684;&#x8111;&#x7EC4;&#x7EC7;&#x4F53;&#x79EF;&#x589E;&#x52A0;&#x3002;&#x540E;&#x9F20;&#x6807;&#x6216;&#x6052;&#x6CB3;&#x7315;&#x7334;&#x8111;&#x76AE;&#x8D28;&#x795E;&#x7ECF;&#x5143;&#xFF0C;ArchT &#x4E5F;&#x5BF9;&#x795E;&#x7ECF;&#x5143;&#x819C;&#xFF0C;&#x8868;&#x793A;&#x8868;&#x8FBE;&#x5F0F;&#x5305;&#x62EC;&#x4F18;&#x79C0;&#x8D29;&#x8FD0;&#x7684;&#x8FDC;&#x8DDD;&#x79BB;&#x4E0B;&#x795E;&#x7ECF;&#x7EC6;&#x80DE;&#x8F74;&#x7A81;&#x3002;&#x9AD8;&#x611F;&#x5149;&#x5EA6;&#x4FC3;&#x4F7F;&#x6211;&#x4EEC;&#x63A2;&#x8BA8;&#x5728;&#x6052;&#x6CB3;&#x7334;&#x5927;&#x8111;&#x76AE;&#x8D28;&#x4E2D;&#x7684; ArchT &#x4F7F;&#x7528;&#x3002;ArchT &#x8868;&#x793A;&#x7684;&#x6E05;&#x9192;&#x7684;&#x7315;&#x7334;&#x5927;&#x8111;&#x4E2D;&#x7684;&#x795E;&#x7ECF;&#x5143;&#x7684;&#x5149;&#x5B66;&#x6444;&#x52A8;&#x5BFC;&#x81F4;&#x5FEB;&#x901F;&#x548C;&#x5B8C;&#x6210; (&sim;100%) &#x6C89;&#x9ED8;&#x7684;&#x5927;&#x591A;&#x6570;&#x8BB0;&#x5F55;&#x7EC6;&#x80DE;&#xFF0C;&#x6291;&#x5236;&#x7EC6;&#x80DE;&#x5B9E;&#x73B0; 0 &#x5CF0;&#x503C;/s &#x65F6;&#x7167;&#x660E;&#x4E2D;&#x4F4D;&#x6570;&#x70E7;&#x6210;&#x7387;&#x3002;&#x4EBA;&#x53E3;&#x5C11;&#x7684;&#x795E;&#x7ECF;&#x5143;&#x8868;&#x660E;&#x589E;&#x52A0;&#x70E7;&#x6210;&#x7387;&#x5728;&#x8F83;&#x957F;&#x7684;&#x5EF6;&#x8FDF;&#x4E4B;&#x540E;&#x7206;&#x53D1;&#x7684;&#x523A;&#x6FC0;&#x65F6;&#xFF0C;&#x5EFA;&#x8BAE;&#x7684;&#x7F51;&#x7EDC;&#x7EA7;&#x795E;&#x7ECF;&#x6D3B;&#x52A8;&#x5E73;&#x8861;&#x673A;&#x5236;&#x7684;&#x5B58;&#x5728;&#x3002;&#x6D3B;&#x52A8;&#x7684;&#x5F3A;&#x5927;&#x51C0;&#x5236;&#x6B62;&#x8868;&#x660E;&#x7684; ArchT &#x6D88;&#x58F0;&#x6280;&#x672F;&#x53EF;&#x80FD;&#x662F;&#x5341;&#x5206;&#x4E0D;&#x53EA;&#x5728;&#x795E;&#x7ECF;&#x7535;&#x8DEF;&#x3001; &#x56E0;&#x679C;&#x5206;&#x6790;&#x4E2D;&#x4F7F;&#x7528;&#xFF0C;&#x4F46;&#x53EF;&#x80FD;&#x6CBB;&#x7597;&#x5E94;&#x7528;&#x3002;

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Technologies for silencing the electrical activity of genetically targeted neurons in the brain are important for assessing the contribution of specific cell types and pathways toward behaviors and pathologies. Recently we found that archaerhodopsin-3 from Halorubrum sodomense (Arch), a light-driven outward proton pump, when genetically expressed in neurons, enables them to be powerfully, transiently, and repeatedly silenced in response to pulses of light. Because of the impressive characteristics of Arch, we explored the optogenetic utility of opsins with high sequence homology to Arch, from archaea of the Halorubrum genus. We found that the archaerhodopsin from Halorubrum strain TP009, which we named ArchT, could mediate photocurrents of similar maximum amplitude to those of Arch (âˆ¼900â€‰pA in vitro), but with a >3-fold improvement in light sensitivity over Arch, most notably in the optogenetic range of 1-10 mW/mm(2), equating to >2Ã— increase in brain tissue volume addressed by a typical single optical fiber. Upon expression in mouse or rhesus macaque cortical neurons, ArchT expressed well on neuronal membranes, including excellent trafficking for long distances down neuronal axons. The high light sensitivity prompted us to explore ArchT use in the cortex of the rhesus macaque. Optical perturbation of ArchT-expressing neurons in the brain of an awake rhesus macaque resulted in a rapid and complete (âˆ¼100%) silencing of most recorded cells, with suppressed cells achieving a median firing rate of 0 spikes/s upon illumination. A small population of neurons showed increased firing rates at long latencies following the onset of light stimulation, suggesting the existence of a mechanism of network-level neural activity balancing. The powerful net suppression of activity suggests that ArchT silencing technology might be of great use not only in the causal analysis of neural circuits, but may have therapeutic applications.

A high-light sensitivity optical neural silencer: development and application to optogenetic control of non-human primate cortex.

Technologies pour r&#xE9;duire au silence l&#x26;#39;activit&#xE9; &#xE9;lectrique des neurones g&#xE9;n&#xE9;tiquement cibl&#xE9;es dans le cerveau sont importantes pour &#xE9;valuer la contribution de types cellulaires sp&#xE9;cifiques et des voies vers des comportements et des pathologies. R&#xE9;cemment, nous avons constat&#xE9; que archaerhodopsin-3 &#xE0; partir Halorubrum sodomense (Arch), une pompe &#xE0; protons lumi&#xE8;re ax&#xE9;e vers l&#x26;#39;ext&#xE9;rieur, quand g&#xE9;n&#xE9;tiquement exprim&#xE9; dans les neurones, leur permet d&#x26;#39;&#xEA;tre puissamment, de mani&#xE8;re transitoire, et &#xE0; plusieurs reprises silence en r&#xE9;ponse &#xE0; des impulsions de lumi&#xE8;re. En raison des caract&#xE9;ristiques impressionnantes de l&#x26;#39;Arche, nous avons explor&#xE9; l&#x26;#39;utilit&#xE9; de optog&#xE9;n&#xE9;tique opsines avec forte homologie de s&#xE9;quence &#xE0; l&#x26;#39;Arche, &#xE0; partir arch&#xE9;es du genre Halorubrum. Nous avons constat&#xE9; que l&#x26;#39;archaerhodopsin de Halorubrum souche TP009, que nous avons nomm&#xE9;e ArchT, pourrait servir de m&#xE9;diateur photocourants d&#x26;#39;amplitude maximale semblables &#xE0; ceux de l&#x26;#39;Arche (~ 900 Pa in vitro), mais avec une am&#xE9;lioration&#x26;gt; 3 fois la sensibilit&#xE9; &#xE0; la lumi&#xE8;re plus Arch, et plus particuli&#xE8;rement dans la plage de optog&#xE9;n&#xE9;tique mW 1-10 / mm (2), qui &#xE9;quivaut &#xE0;&#x26;gt; 2 &#xD7; augmentation du volume du tissu c&#xE9;r&#xE9;bral adress&#xE9;e par une fibre optique type unique. Lors de l&#x26;#39;expression chez la souris ou macaque rh&#xE9;sus neurones corticaux, ArchT exprim&#xE9; ainsi sur les membranes neuronales, y compris la traite excellente sur de longues distances vers le bas axones neuronaux. La sensibilit&#xE9; &#xE0; la lumi&#xE8;re de haute nous a incit&#xE9; &#xE0; explorer l&#x26;#39;utilisation ArchT dans le cortex de l&#x26;#39;macaque rh&#xE9;sus. Perturbation optique de ArchT exprimant neurones dans le cerveau d&#x26;#39;un macaque rh&#xE9;sus &#xE9;veill&#xE9; a entra&#xEE;n&#xE9; une rapide et compl&#xE8;te (~ 100%) au silence de la plupart des cellules enregistr&#xE9;es, avec des cellules supprim&#xE9;es atteindre une cadence de tir moyenne de 0 pointes par seconde lors de l&#x26;#39;illumination. Une petite population de neurones a montr&#xE9; une augmentation des taux de tir &#xE0; longues latences apr&#xE8;s le d&#xE9;but de la stimulation lumineuse, ce qui sugg&#xE8;re l&#x26;#39;existence d&#x26;#39;un m&#xE9;canisme de niveau r&#xE9;seau &#xE9;quilibrage activit&#xE9; neuronale. La suppression nette puissante de l&#x26;#39;activit&#xE9; sugg&#xE8;re que la technologie pourrait &#xEA;tre silencieux ArchT d&#x26;#39;une grande utilit&#xE9; non seulement dans l&#x26;#39;analyse causale des circuits neuronaux, mais peut avoir des applications th&#xE9;rapeutiques.

Une haute sensibilit&#xE9; de lumi&#xE8;re optique Silencieux Neural: D&#xE9;veloppement et application au contr&#xF4;le de optog&#xE9;n&#xE9;tique de primate non humain Cortex

Technologien zum Schweigen zu die elektrische Aktivit&auml;t des genetisch gezielte Neuronen im Gehirn sind wichtig f&uuml;r die Beurteilung des Beitrags der spezifischen Zelltypen und Wege in Richtung Verhaltensweisen und Pathologien. Vor kurzem fanden wir, dass Archaerhodopsin-3 aus Halorubrum Sodomense (Arch), eine Licht-gesteuerte nach au&szlig;en Protonenpumpe, wenn gentechnisch in Neuronen, ausgedr&uuml;ckt sie kraftvoll, vor&uuml;bergehend und wiederholt als Reaktion auf Impulse des Lichtes ausgeschaltet werden kann. Wegen der beeindruckenden Eigenschaften Arch erkundete wir das Optogenetic-Dienstprogramm des Opsins mit hohen Sequenz-Homologie, Arch, von Archaeen der Gattung Halorubrum. Wir fanden, dass die Archaerhodopsin von Halorubrum Stamm TP009, die wir ArchT benannt, Fremdlicht &auml;hnliche maximale Amplitude des Bogens (&sim;900 pA in Vitro), jedoch mit vermitteln k&ouml;nnte ein &gt; 3-Band Verbesserung der Lichtempfindlichkeit &uuml;ber Bogen, vor allem im Optogenetic Bereich von 1-10 mW/mm(2), um die Gleichsetzung &gt; 2 &times; Anstieg Hirnvolumen Gewebe durch eine typische einzige optische Faser behoben. Auf Ausdruck in Maus oder Rhesus-Makak kortikale Neuronen, ArchT gut auf neuronalen Membranen, einschlie&szlig;lich des Handels mit hervorragend f&uuml;r lange Abst&auml;nde hinunter neuronalen Axonen ausgedr&uuml;ckt. Die hohe Lichtempfindlichkeit aufgefordert uns ArchT Verwendung in der Hirnrinde der Rhesusaffe zu erkunden. Optische St&ouml;rung ArchT-Ausdruck von Neuronen im Gehirn von einer wach Rhesusaffe f&uuml;hrte zu einer raschen und abschlie&szlig;en (&sim;100 %) zum Schweigen der meisten aufgezeichneten Zellen, mit unterdr&uuml;ckten Zellen erreichen eine durchschnittliche Feuerrate von 0 Spitzen/s bei der Beleuchtung. Eine kleine Population von Neuronen zeigte erh&ouml;hte feuern Preise bei langen Wartezeiten nach dem Beginn der leichte Stimulation, was auf die Existenz eines Mechanismus auf Netzwerkebene neurale Aktivit&auml;t ausgleichen. Die leistungsstarke net Unterdr&uuml;ckung der Aktivit&auml;t zufolge ArchT silencing Technologie von gro&szlig;en sein kann nicht nur in der kausalen Analyse der neuronalen Schaltkreise verwenden, aber m&ouml;glicherweise therapeutische Anwendungen.

Ein High-Light Empfindlichkeit optische neuronale Schalld&auml;mpfer: Entwicklung und Anwendung Optogenetic Kontrolle der nicht-menschlichen Primaten Kortex.

Tecnologie per silenziare l&#39;attivit&agrave; elettrica dei neuroni geneticamente mirati nel cervello sono importanti per valutare il contributo di tipi cellulari specifici e percorsi verso comportamenti e patologie. Recentemente abbiamo scoperto che archaerhodopsin-3 da Halorubrum sodomense (arco), una pompa di luce-driven protone verso l&#39;esterno, quando geneticamente espresso nei neuroni, permette loro di essere potentemente, transitoriamente e ripetutamente a tacere in risposta agli impulsi di luce. A causa delle caratteristiche impressionanti dell&#39;arco, abbiamo esplorato l&#39;utilit&agrave; di optogenetic di opsins con omologia di sequenza alto ad arco, da archaea del genere Halorubrum. Abbiamo trovato che la archaerhodopsin dal ceppo Halorubrum TP009, che abbiamo chiamato ArchT, potrebbe mediare photocurrents di ampiezza massima simile a quelli dell&#39;arco (pA &sim;900 in vitro), ma con un &amp;gt; triplice miglioramento nella sensibilit&agrave; alla luce sopra l&#39;arco, in particolare nella gamma di 1-10 mW/mm(2), equiparando a optogenetic &amp;gt; 2 &times; aumento di volume del tessuto cerebrale indirizzata da un tipico singola fibra ottica. Su espressione in neuroni corticali del mouse o rhesus macaco, ArchT espresso bene sulle membrane neuronali, compresa la tratta eccellente per lunghe distanze gi&ugrave; assoni neuronali. L&#39;alta sensibilit&agrave; alla luce ci ha spinti a esplorare ArchT uso della corteccia del macaco rhesus. Ottico perturbazione di esprimere ArchT neuroni nel cervello di un macaco rhesus sveglio ha provocato una rapida e completa (% &sim;100) silenziamento delle cellule pi&ugrave; registrate, con cellule soppressione ottenendo un tasso di infornamento mediano di picchi/s 0 all&#39;illuminazione. Una piccola popolazione di neuroni ha mostrato tassi di infornamento aumentato a latenze lunghe dopo l&#39;insorgenza della stimolazione luminosa, suggerendo l&#39;esistenza di un meccanismo di bilanciamento attivit&agrave; neurale a livello di rete. Il potente soppressione netta di attivit&agrave; suggerisce che ArchT silenziamento tecnologia potrebbe essere di grande utilizzare non solo nell&#39;analisi causale dei circuiti neurali, ma pu&ograve; avere applicazioni terapeutiche.

Un silenziatore neurale ottica sensibilit&agrave; high-light: sviluppo e applicazione di controllo optogenetic della corteccia primate non umano.

&#x8133;&#x5185;&#x3067;&#x907A;&#x4F1D;&#x7684;&#x306B;&#x6A19;&#x7684;&#x30CB;&#x200B;&#x200B;&#x30E5;&#x30FC;&#x30ED;&#x30F3;&#x306E;&#x96FB;&#x6C17;&#x7684;&#x6D3B;&#x52D5;&#x3092;&#x9ED9;&#x3089;&#x305B;&#x308B;&#x305F;&#x3081;&#x306E;&#x6280;&#x8853;&#x306F;&#x3001;&#x884C;&#x52D5;&#x3084;&#x75C5;&#x7406;&#x5B66;&#x306B;&#x5411;&#x304B;&#x3063;&#x3066;&#x7279;&#x5B9A;&#x306E;&#x7D30;&#x80DE;&#x578B;&#x3068;&#x7D4C;&#x8DEF;&#x306E;&#x5BC4;&#x4E0E;&#x3092;&#x8A55;&#x4FA1;&#x3059;&#x308B;&#x305F;&#x3081;&#x306B;&#x91CD;&#x8981;&#x3067;&#x3042;&#x308B;&#x3002;&#x6700;&#x8FD1;&#x6211;&#x3005;&#x306F;&#x907A;&#x4F1D;&#x7684;&#x306B;&#x795E;&#x7D4C;&#x7D30;&#x80DE;&#x306B;&#x767A;&#x73FE;Halorubrum sodomense&#xFF08;&#x30A2;&#x30FC;&#x30C1;&#xFF09;&#x306F;&#x3001;&#x5149;&#x99C6;&#x52D5;&#x578B;&#x306E;&#x5916;&#x5074;&#x306B;&#x30D7;&#x30ED;&#x30C8;&#x30F3;&#x30DD;&#x30F3;&#x30D7;&#x3001;&#x3088;&#x308A;archaerhodopsin-3&#x306F;&#x3001;&#x305D;&#x308C;&#x3089;&#x3092;&#x4E00;&#x6642;&#x7684;&#x306B;&#x3001;&#x5F37;&#x529B;&#x3067;&#x3042;&#x308B;&#x3053;&#x3068;&#x304C;&#x53EF;&#x80FD;&#x3068;&#x306A;&#x308A;&#x3001;&#x7E70;&#x308A;&#x8FD4;&#x3057;&#x306E;&#x5149;&#x30D1;&#x30EB;&#x30B9;&#x306B;&#x5FDC;&#x7B54;&#x3057;&#x3066;&#x3001;&#x6C88;&#x9ED9;&#x3053;&#x3068;&#x304C;&#x308F;&#x304B;&#x3063;&#x305F;&#x3002;&#x306E;&#x3067;&#x3001;&#x30A2;&#x30FC;&#x30C1;&#x306E;&#x5370;&#x8C61;&#x7684;&#x306A;&#x7279;&#x6027;&#x304B;&#x3089;&#x3001;&#x6211;&#x3005;&#x306F;Halorubrum&#x5C5E;&#x306E;&#x7D30;&#x83CC;&#x304B;&#x3089;&#x3001;&#x30A2;&#x30FC;&#x30C1;&#x306E;&#x9AD8;&#x3044;&#x914D;&#x5217;&#x76F8;&#x540C;&#x6027;&#x3068;&#x30AA;&#x30D7;&#x30B7;&#x30F3;&#x306E;optogenetic&#x30E6;&#x30FC;&#x30C6;&#x30A3;&#x30EA;&#x30C6;&#x30A3;&#x3092;&#x63A2;&#x3063;&#x305F;&#x3002;&#x6211;&#x3005;&#x306F;ArchT&#x540D;&#x524D;Halorubrum&#x3072;&#x305A;&#x307F;TP009&#x3001;&#x3088;&#x308A;archaerhodopsin&#x304C;&#x30A2;&#x30FC;&#x30C1;&#x3057;&#x305F;&#xFF08;in vitro&#x301C;900 Pa&#xFF09;&#x306E;&#x3082;&#x306E;&#x306B;&#x985E;&#x4F3C;&#x3057;&#x305F;&#x6700;&#x5927;&#x632F;&#x5E45;&#x306E;&#x5149;&#x96FB;&#x6D41;&#x3092;&#x5A92;&#x4ECB;&#x3059;&#x308B;&#x3053;&#x3068;&#x304C;&#x308F;&#x304B;&#x3063;&#x305F;&#x304C;&#x3001;&#x6700;&#x3082;&#x9855;&#x8457;&#x306A;&#x30A2;&#x30FC;&#x30C1;&#x3001;&#x4E0A;&#x306E;&#x5149;&#x611F;&#x5EA6;&#x306E;&#x26;gt; 3&#x500D;&#x306E;&#x6539;&#x5584;&#x3068;1&#x304B;&#x3089;10 MW /&#x30DF;&#x30EA;&#x30E1;&#x30FC;&#x30C8;&#x30EB;&#xFF08;2&#xFF09;&#x306E;optogenetic&#x7BC4;&#x56F2;&#x3067;&#x3001;&#x5178;&#x578B;&#x7684;&#x306A;&#x5358;&#x4E00;&#x306E;&#x5149;&#x30D5;&#x30A1;&#x30A4;&#x30D0;&#x306B;&#x3088;&#x3063;&#x3066;&#x5BFE;&#x51E6;&#x8133;&#x7D44;&#x7E54;&#x306E;&#x5BB9;&#x7A4D;&#x306E;&#x26;gt; 2&#x500D;&#x306E;&#x5897;&#x52A0;&#x306B;&#x7B49;&#x3057;&#x3044;&#x3068;&#x3002;&#x30DE;&#x30A6;&#x30B9;&#x3084;&#x30A2;&#x30AB;&#x30B2;&#x30B6;&#x30EB;&#x76AE;&#x8CEA;&#x30CB;&#x30E5;&#x30FC;&#x30ED;&#x30F3;&#x3067;&#x306E;&#x767A;&#x73FE;&#x6642;&#x306B;&#x3001;ArchT&#x306F;&#x3001;&#x795E;&#x7D4C;&#x8EF8;&#x7D22;&#x30C0;&#x30A6;&#x30F3;&#x9577;&#x8DDD;&#x96E2;&#x306E;&#x305F;&#x3081;&#x306E;&#x512A;&#x308C;&#x305F;&#x4EBA;&#x8EAB;&#x58F2;&#x8CB7;&#x3092;&#x542B;&#x3080;&#x795E;&#x7D4C;&#x7D30;&#x80DE;&#x819C;&#x4E0A;&#x306B;&#x3082;&#x8868;&#x660E;&#x3057;&#x305F;&#x3002;&#x9AD8;&#x3044;&#x5149;&#x611F;&#x5EA6;&#x306F;&#x3001;&#x30A2;&#x30AB;&#x30B2;&#x30B6;&#x30EB;&#x306E;&#x5927;&#x8133;&#x76AE;&#x8CEA;&#x3067;ArchT&#x4F7F;&#x7528;&#x3092;&#x691C;&#x8A0E;&#x3059;&#x308B;&#x3053;&#x3068;&#x304C;&#x6C42;&#x200B;&#x200B;&#x3081;&#x3089;&#x308C;&#x307E;&#x3059;&#x3002; ArchT&#x767A;&#x73FE;&#x30A2;&#x30AB;&#x30B2;&#x30B6;&#x30EB;&#x899A;&#x9192;&#x306E;&#x8133;&#x5185;&#x306E;&#x795E;&#x7D4C;&#x7D30;&#x80DE;&#x306E;&#x5149;&#x6442;&#x52D5;&#x3092;&#x6291;&#x5236;&#x3057;&#x3001;&#x7D30;&#x80DE;&#x304C;&#x7167;&#x660E;&#x6642;&#x306B;&#x306F;0&#x30B9;&#x30D1;&#x30A4;&#x30AF;/&#x79D2;&#x306E;&#x5E73;&#x5747;&#x7684;&#x306A;&#x767A;&#x706B;&#x7387;&#x3092;&#x9054;&#x6210;&#x3059;&#x308B;&#x305F;&#x3081;&#x306B;&#x3001;&#x307B;&#x3068;&#x3093;&#x3069;&#x8A18;&#x9332;&#x3055;&#x308C;&#x305F;&#x7D30;&#x80DE;&#x306E;&#x8FC5;&#x901F;&#x304B;&#x3064;&#x5B8C;&#x5168;&#x306A;&#xFF08;&#x301C;100&#xFF05;&#xFF09;&#x30B5;&#x30A4;&#x30EC;&#x30F3;&#x30B7;&#x30F3;&#x30B0;&#x3092;&#x3082;&#x305F;&#x3089;&#x3057;&#x305F;&#x3002;&#x795E;&#x7D4C;&#x7D30;&#x80DE;&#x306E;&#x5C0F;&#x96C6;&#x56E3;&#x306F;&#x3001;&#x30CD;&#x30C3;&#x30C8;&#x30EF;&#x30FC;&#x30AF;&#xB7;&#x30EC;&#x30D9;&#x30EB;&#x306E;&#x795E;&#x7D4C;&#x6D3B;&#x52D5;&#x306E;&#x30D0;&#x30E9;&#x30F3;&#x30B9;&#x306E;&#x30E1;&#x30AB;&#x30CB;&#x30BA;&#x30E0;&#x306E;&#x5B58;&#x5728;&#x3092;&#x793A;&#x5506;&#x3057;&#x3001;&#x5149;&#x523A;&#x6FC0;&#x306E;&#x767A;&#x75C7;&#x5F8C;&#x9577;&#x3044;&#x5F85;&#x3061;&#x6642;&#x9593;&#x3067;&#x5897;&#x52A0;&#x3057;&#x3066;&#x767A;&#x706B;&#x7387;&#x3092;&#x793A;&#x3057;&#x305F;&#x3002;&#x6D3B;&#x52D5;&#x306E;&#x5F37;&#x529B;&#x306A;&#x30CD;&#x30C3;&#x30C8;&#x6291;&#x5236;&#x306F;&#x3001;&#x305D;&#x306E;ArchT&#x30B5;&#x30A4;&#x30EC;&#x30F3;&#x30B7;&#x30F3;&#x30B0;&#x6280;&#x8853;&#x306F;&#x3001;&#x795E;&#x7D4C;&#x56DE;&#x8DEF;&#x306E;&#x56E0;&#x679C;&#x95A2;&#x4FC2;&#x306E;&#x5206;&#x6790;&#x3060;&#x3051;&#x3067;&#x306A;&#x304F;&#x3068;&#x3066;&#x3082;&#x4FBF;&#x5229;&#x304B;&#x3082;&#x3057;&#x308C;&#x307E;&#x305B;&#x3093;&#x304C;&#x3001;&#x6CBB;&#x7642;&#x3078;&#x306E;&#x5FDC;&#x7528;&#x3092;&#x6301;&#x3063;&#x3066;&#x3044;&#x308B;&#x3053;&#x3068;&#x3092;&#x793A;&#x5506;&#x3057;&#x3066;&#x3044;&#x308B;&#x3002;

&#x9AD8;&#x5149;&#x611F;&#x5EA6;&#x5149;&#x30CB;&#x30E5;&#x30FC;&#x30E9;&#x30EB;&#x30B5;&#x30A4;&#x30EC;&#x30F3;&#x30B5;&#x30FC;&#xFF1A;&#x975E;&#x30D2;&#x30C8;&#x970A;&#x9577;&#x985E;&#x76AE;&#x8CEA;&#x306E;Optogenetic&#x5236;&#x5FA1;&#x3078;&#x306E;&#x958B;&#x767A;&#x3068;&#x305D;&#x306E;&#x5FDC;&#x7528;

&#xC785;&#xC744; &#xB1CC; &#xC720;&#xC804;&#xC790; &#xD0C0;&#xAC9F;&#xB41C; &#xB274;&#xB7F0;&#xC758; &#xC804;&#xAE30; &#xD65C;&#xB3D9;&#xC5D0; &#xB300; &#xD55C; &#xAE30;&#xC220; &#xD2B9;&#xC815; &#xC140; &#xC885;&#xB958;&#xC640; &#xB3D9;&#xC791; &#xBC0F; pathologies &#xD1B5;&#xB85C;&#xC758; &#xAE30;&#xC5EC;&#xB97C; &#xD3C9;&#xAC00; &#xD558;&#xAE30; &#xC704;&#xD55C; &#xC911;&#xC694; &#xD558;&#xB2E4;. &#xC6B0;&#xB9AC;&#xAC00; &#xADF8;&#xB4E4;&#xC744; &#xAC15;&#xB825; &#xD558; &#xAC8C;, transiently, &#xADF8;&#xB9AC;&#xACE0; &#xBC18;&#xBCF5;&#xC801;&#xC73C;&#xB85C; &#xB2F9;&#xD560; &#xBE5B;&#xC758; &#xD384;&#xC2A4;&#xC5D0; &#xB300; &#xD55C; &#xC751;&#xB2F5;&#xC5D0; &#xBE5B; &#xC911;&#xC2EC; &#xBC14;&#xAE65;&#xCABD;&#xC73C;&#xB85C; &#xC591;&#xC131;&#xC790; &#xD38C;&#xD504;, &#xC2E0;&#xACBD; &#xC138;&#xD3EC;, &#xC720;&#xC804;&#xC790;&#xB85C; &#xD45C;&#xD604; &#xD558;&#xB294; &#xACBD;&#xC6B0; &#xC218;&#xB97C; archaerhodopsin-3 Halorubrum sodomense (&#xC544;&#xCE58;)&#xC5D0;&#xC11C; &#xADF8;&#xB294; &#xCD5C;&#xADFC;&#xC5D0; &#xBC1C;&#xACAC;. &#xC778;&#xC0C1;&#xC801;&#xC778; &#xC544;&#xCE58; &#xD2B9;&#xC131;&#xC0C1; &#xC6B0;&#xB9AC; Halorubrum &#xC18D;&#xC758; &#xACE0;&#xC138;&#xADE0;&#xC5D0;&#xC11C; &#xC544;&#xCE58;, &#xB192;&#xC740; &#xC2DC;&#xD000;&#xC2A4; homology&#xC640; opsins&#xC758; optogenetic &#xC720;&#xD2F8;&#xB9AC;&#xD2F0;&#xB97C; &#xD0D0;&#xD5D8;. &#xC6B0;&#xB9AC; &#xB77C;&#xB294; ArchT, Halorubrum TP009, &#xC2A4;&#xD2B8;&#xB808;&#xC778;&#xC5D0;&#xC11C; archaerhodopsin photocurrents &#xC544;&#xCE58; (&sim;900 pA &#xC2DC;&#xD5D8;&#xAD00;), &#xD558;&#xC9C0;&#xB9CC; &#xC0AC;&#xB78C;&#xB4E4;&#xC5D0; &#xAC8C; &#xBE44;&#xC2B7;&#xD55C; &#xCD5C;&#xB300; &#xC9C4;&#xD3ED;&#xC758; &#xC911;&#xC7AC; &#xC218;&#xB97C; &#xCC3E;&#xC558;&#xC2B5;&#xB2C8;&#xB2E4;.&#xB294; &amp;gt; &#xC544;&#xCE58;, &#xC704;&#xC5D0; &#xBE5B;&#xC774; &#xAC10;&#xB3C4;&#xB97C; &#xB3D9;&#xC77C;&#xC2DC; &#xD558;&#xB294; 1-10 mW/mm(2) optogenetic &#xBC94;&#xC704;&#xC5D0;&#xC11C; &#xAC00;&#xC7A5; &#xC8FC;&#xBAA9;&#xD560; &#xB9CC;&#xD55C; 3 &#xAC1C;&#xC120; &amp;gt; 2 &times; &#xC99D;&#xAC00; &#xB1CC; &#xC870;&#xC9C1; &#xBCFC;&#xB968; &#xC804;&#xD615;&#xC801;&#xC778; &#xB2E8;&#xC77C; &#xAD11;&#xC12C;&#xC720;&#xC5D0; &#xC758;&#xD574; &#xD574;&#xACB0;. &#xC2DD; &#xB9C8;&#xC6B0;&#xC2A4; &#xB610;&#xB294; &#xBD89;&#xC740; &#xD138; &#xC6D0;&#xC22D;&#xC774; &#xB300;&#xB1CC; &#xD53C; &#xC9C8;&#xC758; &#xB274;&#xB7F0;, &#xC2E0;&#xACBD; &#xCD95; &#xC0AD; &#xB0B4;&#xB824; &#xAE34; &#xAC70;&#xB9AC;&#xC5D0; &#xB300; &#xD55C; &#xC6B0;&#xC218;&#xD55C; &#xC778;&#xC2E0; &#xB9E4;&#xB9E4;&#xB97C; &#xD3EC;&#xD568; &#xD55C; &#xC2E0;&#xACBD; &#xC138;&#xD3EC; &#xB9C9;&#xC5D0; &#xC798; &#xD45C;&#xD604; &#xD558;&#xB294; ArchT. &#xB192;&#xC740; &#xBE5B;&#xC774; &#xAC10;&#xB3C4; &#xBD89;&#xC740; &#xD138; &#xC6D0;&#xC22D;&#xC774;&#xC758; &#xD53C; &#xC9C8;&#xC5D0;&#xC11C; ArchT &#xC0AC;&#xC6A9; &#xCC3E;&#xC544;&#xBCF4;&#xAE30; &#xC6B0;&#xB9AC;&#xB97C; &#xBB3B;&#xB294; &#xBA54;&#xC2DC;&#xC9C0;&#xAC00;. ArchT &#xD45C;&#xD604; &#xAE68;&#xC5B4; &#xBD89;&#xC740; &#xD138; &#xC6D0;&#xC22D;&#xC774;&#xC758; &#xB1CC;&#xC5D0;&#xC11C; &#xB274;&#xB7F0;&#xC758; &#xAD11; &#xC12D; &#xB3D9; &#xBE60;&#xB978; &#xACB0;&#xACFC; (&sim;100%) &#xC5B5;&#xC81C; &#xC138;&#xD3EC; &#xC870;&#xBA85;&#xC5D0; &#xB530;&#xB77C; 0 &#xC2A4;&#xD30C;&#xC774;&#xD06C;/s&#xC758; &#xD3C9;&#xADE0; &#xBC1C;&#xC0AC; &#xC18D;&#xB3C4; &#xB2EC;&#xC131; &#xD568;&#xAED8; &#xAC00;&#xC7A5; &#xAE30;&#xB85D; &#xB41C; &#xC140;&#xC758; &#xC785;&#xC744; &#xC644;&#xB8CC;. &#xC2E0;&#xACBD; &#xC138;&#xD3EC;&#xC758; &#xC791;&#xC740; &#xC778;&#xAD6C; &#xADE0;&#xD615;&#xC744; &#xC870;&#xC815; &#xD558;&#xB294; &#xB124;&#xD2B8;&#xC6CC;&#xD06C; &#xC218;&#xC900;&#xC758; &#xC2E0;&#xACBD; &#xD65C;&#xB3D9; &#xBA54;&#xCEE4;&#xB2C8;&#xC998;&#xC758; &#xC874;&#xC7AC;&#xB97C; &#xC81C;&#xC548; &#xAC00;&#xBCBC;&#xC6B4; &#xC790;&#xADF9;&#xC758; &#xAC1C;&#xC2DC;&#xC5D0; &#xB530;&#xB77C; &#xAE34; &#xB300;&#xAE30; &#xC2DC;&#xAC04;&#xC5D0; &#xC99D;&#xAC00; &#xB41C; &#xBC1C;&#xC0AC; &#xC18D;&#xB3C4; &#xBCF4;&#xC600;&#xB2E4;. &#xD65C;&#xB3D9;&#xC758; &#xAC15;&#xB825;&#xD55C; net &#xC5B5;&#xC81C; &#xC81C;&#xC548; ArchT silencing &#xAE30;&#xC220; &#xC704;&#xB300;&#xD55C; &#xB420; &#xBFD0;&#xB9CC; &#xC544;&#xB2C8;&#xB77C; &#xC2E0;&#xACBD; &#xD68C;&#xB85C;&#xC758; &#xC778;&#xACFC; &#xBD84;&#xC11D;&#xC5D0;&#xC5D0;&#xC11C; &#xC0AC;&#xC6A9; &#xD558;&#xC9C0;&#xB9CC; &#xCE58;&#xB8CC; &#xC751;&#xC6A9; &#xD504;&#xB85C;&#xADF8;&#xB7A8;&#xC744; &#xD560; &#xC218; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;.

&#xB192;&#xC740; &#xBE5B; &#xAC10;&#xB3C4; &#xAD11;&#xD559; &#xC2E0;&#xACBD; &#xC18C;&#xC74C; &#xAE30;: &#xAC1C;&#xBC1C; &#xBC0F; &#xBE44; &#xC778;&#xAC04; &#xC601;&#xC7A5;&#xB958; &#xD53C; &#xC9C8; optogenetic &#xCEE8;&#xD2B8;&#xB864;&#xC744; &#xC751;&#xC6A9; &#xD504;&#xB85C;&#xADF8;&#xB7A8;.

Tecnolog&#xED;as para silenciar la actividad el&#xE9;ctrica de las neuronas gen&#xE9;ticamente espec&#xED;ficas en el cerebro son importantes para evaluar la contribuci&#xF3;n de determinados tipos de c&#xE9;lulas y las v&#xED;as hacia los comportamientos y patolog&#xED;as. Recientemente hemos descubierto que archaerhodopsin-3 de Halorubrum sodomense (Arco), una bomba de protones impulsada por la luz hacia el exterior, cuando la expresi&#xF3;n gen&#xE9;tica en las neuronas, les permite ser de gran alcance, de forma transitoria, y en repetidas ocasiones silencio en respuesta a los pulsos de luz. Debido a las caracter&#xED;sticas impresionantes de Arco, se explor&#xF3; la utilidad de la optogen&#xE9;tica opsinas con alta homolog&#xED;a de secuencia de Arco, de las arqueas del g&#xE9;nero Halorubrum. Se encontr&#xF3; que la cepa archaerhodopsin de Halorubrum TP009, que hemos llamado ArchT, podr&#xED;a mediar fotocorrientes de amplitud m&#xE1;xima similares a los de arco (~ 900 pA in vitro), pero con una mejora&#x26;gt; 3-pliegue en sensibilidad a la luz sobre el arco, lo m&#xE1;s notablemente en el rango de optogen&#xE9;tica de 1-10 mW / mm (2), lo que equivale a&#x26;gt; 2 &#xD7; aumento en el volumen de tejido cerebral dirigida por una sola fibra &#xF3;ptica t&#xED;pica. Tras la expresi&#xF3;n en las neuronas corticales del rat&#xF3;n o macacos rhesus, ArchT bien expresada en las membranas neuronales, incluido el tr&#xE1;fico excelente para las largas distancias por los axones neuronales. La alta sensibilidad a la luz, nos llev&#xF3; a explorar el uso ArchT en la corteza del macaco rhesus. Perturbaci&#xF3;n &#xF3;ptica de ArchT-expresi&#xF3;n de las neuronas en el cerebro de un despierto Macaca mulatta result&#xF3; en un r&#xE1;pido y completo (~ 100%) silenciamiento de la mayor&#xED;a de las c&#xE9;lulas grabadas, con c&#xE9;lulas suprimidas lograr una tasa de disparos mediana de 0 espigas / s sobre la iluminaci&#xF3;n. Una peque&#xF1;a poblaci&#xF3;n de neuronas mostraron un incremento en las tasas de disparo con latencias largas despu&#xE9;s de la aparici&#xF3;n de la estimulaci&#xF3;n de la luz, lo que sugiere la existencia de un mecanismo de equilibrio de la red-el nivel de actividad neuronal. La supresi&#xF3;n de gran alcance neto de la actividad sugiere que la tecnolog&#xED;a de silenciamiento ArchT podr&#xED;a ser de gran utilidad no s&#xF3;lo en el an&#xE1;lisis causal de los circuitos neuronales, pero puede tener aplicaciones terap&#xE9;uticas.

Una alta sensibilidad de la luz &#xF3;ptica Silenciador Neural: Desarrollo y aplicaci&#xF3;n al control de optogen&#xE9;tica de primate no humano Cortex

Activation of dopamine receptors in forebrain regions, for minutes or longer, is known to be sufficient for positive reinforcement of stimuli and actions. However, the firing rate of dopamine neurons is increased for only about 200 milliseconds following natural reward events that are better than expected, a response which has been described as a "reward prediction error" (RPE). Although RPE drives reinforcement learning (RL) in computational models, it has not been possible to directly test whether the transient dopamine signal actually drives RL. Here we have performed optical stimulation of genetically targeted ventral tegmental area (VTA) dopamine neurons expressing Channelrhodopsin-2 (ChR2) in mice. We mimicked the transient activation of dopamine neurons that occurs in response to natural reward by applying a light pulse of 200 ms in VTA. When a single light pulse followed each self-initiated nose poke, it was sufficient in itself to cause operant reinforcement. Furthermore, when optical stimulation was delivered in separate sessions according to a predetermined pattern, it increased locomotion and contralateral rotations, behaviors that are known to result from activation of dopamine neurons. All three of the optically induced operant and locomotor behaviors were tightly correlated with the number of VTA dopamine neurons that expressed ChR2, providing additional evidence that the behavioral responses were caused by activation of dopamine neurons. These results provide strong evidence that the transient activation of dopamine neurons provides a functional reward signal that drives learning, in support of RL theories of dopamine function.

Michael V. Baratta

Institute for Behavioral Genetics,
Department of Psychology and Neuroscience

University of Colorado Boulder

A Method for High Fidelity Optogenetic Control of Individual Pyramidal Neurons In vivo

Michael V. Baratta

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Institute for Behavioral Genetics,Department of Psychology and Neuroscience

University of Colorado Boulder

A Method for High Fidelity Optogenetic Control of Individual Pyramidal Neurons In vivo

Institute for Behavioral Genetics,
Department of Psychology and Neuroscience