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Deisseroth, K.

Publications and source records attributed to Deisseroth, K..

At least 55 records · Page 3Linked to original sources

CLARITY increases sensitivity and specificity of fluorescence immunostaining in long-term archived human brain tissue

Immunohistochemistry on archival human brains is often limited because several conditions arise that complicate the use for high-resolution fluorescence microscopy. In this study, we developed a novel clearing approach for immunofluorescence-based analysis of perfusion- and immersion-fixed post mortem human brain tissue, termed hCLARITY. hCLARITY is optimized for specificity by reducing off-target labeling and yields very sensitive stainings in human brain sections allowing for super-resolution microscopy with unprecedented imaging of pre- and postsynaptic compartments. Moreover, hallmarks of the Alzheimers disease were preserved with hCLARITY, and importantly classical DAB or Nissl stainings are compatible with this protocol. hCLARITY is extremely versatile as demonstrated by the use of more than 30 well performing antibodies and allows for de- and subsequent re-staining of the same tissue section, which is important for multi-labelling approaches, e.g., in super-resolution microscopy. Taken together, hCLARITY enables research of the human brain with highest sensitivity and down to sub-diffraction resolution and therefore has enormous potential for the investigation of local morphological changes, e.g., in neurodegenerative diseases. Striking Image / Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/489700v1_ufig1.gif" ALT="Figure 1"> View larger version (79K): org.highwire.dtl.DTLVardef@1732df2org.highwire.dtl.DTLVardef@cda615org.highwire.dtl.DTLVardef@152b44aorg.highwire.dtl.DTLVardef@ba972a_HPS_FORMAT_FIGEXP M_FIG Summary of the main advantages of hCLARITY. CLARITY was applied on human post mortem brain tissue in direct comparison to untreated sections (minus CLARITY). Owing to removal of lipids during the clearing with SDS and the resulting reduction in light scattering, cleared sections were less opaque. The denaturing effect of the detergent SDS most likely results in better accessibility of certain epitopes. The major benefits of hCLARITY were found in an increased sensitivity and specificity of antibodies for neuronal cells. The adapted hCLARITY protocol is compatible with staining techniques for confocal microscopy, super-resolution microscopy, and light microscopy. C_FIG

neuroscience↗

Topological supramolecular network enabled highly conductive and stretchable organic bioelectronics

Intrinsically stretchable bioelectronic devices based on soft and conducting organic materials have been regarded as the ideal interface for seamless and biocompatible integration with the human body. However, the grand challenge remains for the conducting polymer to possess both high mechanical ductility and good electrical conduction at cellular level feature sizes. This longstanding material limitation in organic bioelectronics has impeded the full exploitation of its unique benefits. Here, we introduce a new molecular engineering strategy based on rationally designed topological supramolecular networks, which allows effective decoupling of competing effects from multiple molecular building blocks to meet complex requirements. We achieve two orders of magnitude improvement in the conductivity under 100% strain in physiological environment, along with the capability for direct photopatterning down to 2 m. These unprecedented capabilities allow us to realize previously inaccessible bioelectronic applications including high-resolution monitoring of soft and malleable creatures, e.g., octopus, and localized neuromodulation down to single nucleus precision for controlling organ-specific activities through delicate tissues, e.g., brainstem.

bioengineering↗

All-optical electrophysiology with improved genetically encoded voltage indicators reveals interneuron network dynamics in vivo

All-optical electrophysiology can be a powerful tool for studying neural dynamics in vivo, as it offers the ability to image and perturb membrane voltage in multiple cells simultaneously. The "Optopatch" constructs combine a red-shifted archaerhodopsin (Arch)-derived genetically encoded voltage indicator (GEVI) with a blue-shifted channelrhodopsin actuator (ChR). We used a video-based pooled screen to evolve Arch-derived GEVIs with improved signal-to-noise ratio (QuasAr6a) and kinetics (QuasAr6b). By combining optogenetic stimulation of individual cells with high-precision voltage imaging in neighboring cells, we mapped inhibitory and gap junction-mediated connections, in vivo. Optogenetic activation of a single NDNF-expressing neuron in visual cortex Layer 1 significantly suppressed the spike rate in some neighboring NDNF interneurons. Hippocampal PV cells showed near-synchronous spikes across multiple cells at a frequency significantly above what one would expect from independent spiking, suggesting that collective inhibitory spikes may play an important signaling role in vivo. By stimulating individual cells and recording from neighbors, we quantified gap junction coupling strengths. Together, these results demonstrate powerful new tools for all-optical microcircuit dissection in live mice.

neuroscience↗

Structural basis for channel conduction in the pump-like channelrhodopsin ChRmine

ChRmine1, a recently-discovered bacteriorhodopsin-like cation-conducting channelrhodopsin1, 2, exhibits puzzling properties (unusually-large photocurrents, exceptional red-shift in action spectrum, and extreme light-sensitivity) that have opened up new opportunities in optogenetics1, 3-5. ChRmine and its homologs function as light-gated ion channels, but by primary sequence more closely resemble ion pump rhodopsins; the molecular mechanisms for passive channel conduction in this family of proteins, as well as the unusual properties of ChRmine itself, have remained mysterious. Here we present the cryo-electron microscopy structure of ChRmine at 2.0 [A] resolution. The structure reveals striking architectural features never seen before in channelrhodopsins including trimeric assembly, a short transmembrane-helix 3 unwound in the middle of the membrane, a prominently-twisting extracellular-loop 1, remarkably-large intracellular cavities and extracellular vestibule, and an unprecedented hydrophilic pore that extends through the center of the trimer, separate from the three individual monomer pores. Electrophysiological, spectroscopic, and computational analyses provide insight into conduction and gating of light-gated channels with these distinct design features, and point the way toward structure-guided creation of novel channelrhodopsins for optogenetic applications in biology.

biophysics↗

Similar neural and perceptual masking effects of low-power optogenetic stimulation in primate V1

Can direct stimulation of primate V1 substitute for a visual stimulus and mimic its perceptual effect? To address this question, we developed an optical-genetic toolkit to "read" neural population responses using widefield calcium imaging, while simultaneously using optogenetics to "write" neural responses into V1 of behaving macaques. We focused on the phenomenon of visual masking, where detection of a dim target is significantly reduced by a co-localized medium-brightness pedestal. Using our toolkit, we tested whether V1 optogenetic stimulation can recapitulate the perceptual masking effect of a visual pedestal. We find that, similar to a visual pedestal, low-power optostimulation can significantly reduce visual detection sensitivity, that a sublinear interaction between visual and optogenetic evoked V1 responses could account for this perceptual effect, and that these neural and behavioral effects are spatially selective. Our toolkit and results open the door for further exploration of perceptual substitutions by direct stimulation of sensory cortex.

neuroscience↗

CloudReg: Automatic Terabyte-Scale Cross-Modal Brain Volume Registration

Quantifying terabyte-scale multi-modal human and animal imaging data requires scalable analysis tools. We developed CloudReg, an open-source, automatic, terabyte-scale, cloud-based image analysis pipeline that pre-processes and registers cross-modal volumetric datasets with artifacts via spatially-varying polynomial intensity transform. CloudReg accurately registers the following datasets to their respective atlases: in vivo human and ex vivo macaque brain magnetic resonance imaging, ex vivo mouse brain micro-computed tomography, and cleared murine brain light-sheet microscopy.

bioengineering↗

Optogenetic activation of Gq signaling in astrocytes yields stimulation-specific effects on basal hippocampal synaptic excitation and inhibition

Astrocytes play active roles at synapses and can monitor, respond, and adapt to local synaptic activity. To investigate this relationship, more tools that can selectively activate native G protein signaling pathways in astrocytes with both spatial and temporal precision are needed. Here, we tested AAV8-GFAP-Opto1AR-eYFP (Opto1AR), a viral vector to enable activation of Gq signaling in astrocytes via light-sensitive 1-adrenergic receptors. To determine if stimulating astrocytic Opto1AR modulates hippocampal synaptic transmission, recordings were made in CA1 pyramidal cells with surrounding astrocytes expressing Opto1AR, channelrhodopsin (ChR2), or GFP. Both high-frequency (20 Hz, 45-ms light pulses, 5 mW, 5 min) and low-frequency (0.5 Hz, 1-s pulses at increasing 1, 5, and 10 mW intensities, 90 s per intensity) blue light stimulation were tested. 20 Hz Opto1AR stimulation increased both inhibitory and excitatory postsynaptic current (IPSC and EPSC) frequency, and the mIPSC effect was largely reversible within 20 min. By contrast, low-frequency stimulation of Opto1AR did not modulate either IPSCs or EPSCs, whereas the same stimulation of astrocytic ChR2 was effective. These data demonstrate that Opto1AR activation in astrocytes changes synaptic excitation and inhibition in a stimulation-sensitive manner, demonstrating the efficacy and utility of GFAP-Opto1AR as a tool in studying astrocyte-neuron interactions.

neuroscience↗

A molecular calcium integrator reveals a striatal cell-type driving aversion

The ability to record transient cellular events in the DNA or RNA of cells would enable precise, large-scale analysis, selection, and reprogramming of heterogeneous cell populations. Here we report a molecular technology for stable genetic tagging of cells that exhibit activity-related increases in intracellular calcium concentration (FLiCRE). We used FLiCRE to transcriptionally label activated neural ensembles in the nucleus accumbens of the mouse brain during brief stimulation of aversive inputs. Using single-cell RNA sequencing, we detected FLiCRE transcripts among the endogenous transcriptome, providing simultaneous readout of both cell-type and calcium activation history. We identified a cell-type in the nucleus accumbens activated downstream of long-range excitatory projections. Taking advantage of FLiCREs modular design, we expressed an optogenetic channel selectively in this cell-type, and showed that direct recruitment of this otherwise genetically-inaccessible population elicits behavioral aversion. The specificity and minute-resolution of FLiCRE enables molecularly-informed characterization, manipulation, and reprogramming of activated cellular ensembles.

neuroscience↗

Higher-order hub cells involved in feedforward motifs as critical factors in epileptic network instability

Neurological and psychiatric disorders are associated with pathological neural dynamics. The fundamental connectivity patterns of cell-cell communication networks that enable pathological dynamics to emerge remain unknown. We studied epileptic circuits using a newly developed integrated computational pipeline applied to cellular resolution functional imaging data. Control and preseizure neural dynamics in larval zebrafish and in chronically epileptic mice were captured using large-scale cellular-resolution calcium imaging. Biologically constrained effective connectivity modeling extracted the underlying cell-cell communication network. Novel analysis of the higher-order network structure revealed the existence of superhub cells that are unusually richly connected to the rest of the network through feedforward motifs. Instability in epileptic networks was causally linked to superhubs whose involvement in feedforward motifs critically enhanced downstream excitation. Disconnecting individual superhubs was significantly more effective in stabilizing epileptic networks compared to disconnecting hub cells defined traditionally by connection count. Collectively, these results predict a new, maximally selective and minimally invasive cellular target for seizure control. HighlightsO_LIHigher-order connectivity patterns of large-scale neuronal communication networks were studied in zebrafish and mice C_LIO_LIControl and epileptic networks were modeled from in vivo cellular resolution calcium imaging data C_LIO_LIRare superhub cells unusually richly connected to the rest of the network through higher-order feedforward motifs were identified C_LIO_LIDisconnecting single superhub neurons more effectively stabilized epileptic networks than targeting conventional hub cells defined by high connection count. C_LIO_LIThese data predict a maximally selective novel single cell target for minimally invasive seizure control C_LI

neuroscience↗

Cerebellar nuclei evolved by repeatedly duplicating a conserved cell type set

How have complex brains evolved from simple circuits? Here we investigated brain region evolution at cell type resolution in the cerebellar nuclei (CN), the output structures of the cerebellum. Using single-nucleus RNA sequencing in mice, chickens, and humans, as well as STARmap spatial transcriptomic analysis and whole-CNS projection tracing in mice, we identified a conserved cell type set containing two classes of region-specific excitatory neurons and three classes of region-invariant inhibitory neurons. This set constitutes an archetypal CN that was repeatedly duplicated to form new regions. Interestingly, the excitatory cell class that preferentially funnels information to lateral frontal cortices in mice becomes predominant in the massively expanded human Lateral CN. Our data provide the first characterization of CN transcriptomic cell types in three species and suggest a model of brain region evolution by duplication and divergence of entire cell type sets.

neuroscience↗

A unique and evolutionarily conserved retinal interneuron relays rod and cone input to the inner plexiform layer

Neurons in the CNS are distinguished from each other by their morphology, the types of the neurotransmitter they release, their synaptic connections, and their genetic profiles. While attempting to characterize the retinal bipolar cell (BC) input to retinal ganglion cells (RGCs), we discovered a previously undescribed type of interneuron in mice and primates. This interneuron shares some morphological, physiological, and molecular features with traditional BCs, such as having dendrites that ramify in the outer plexiform layer (OPL) and axons that ramify in the inner plexiform layer (IPL) to relay visual signals from photoreceptors to inner retinal neurons. It also shares some features with amacrine cells, particularly Aii amacrine cells, such as their axonal morphology and possibly the release of the inhibitory neurotransmitter glycine, along with the expression of some amacrine cell specific markers. Thus, we unveil an unrecognized type of interneuron, which may play unique roles in vision. Significance StatementCell types are the building blocks upon which neural circuitry is based. In the retina, it is widely believed that all neuronal types have been identified. We describe a cell type, which we call the Campana cell, that does not fit into the conventional neuronal retina categories but is evolutionarily conserved. Unlike retinal bipolar cells, the Campana cell receives synaptic input from both rods and cones, has broad axonal ramifications, and may release an inhibitory neurotransmitter. Unlike retinal amacrine cells, the Campana cell receives direct photoreceptor input has bipolar-like ribbon synapses. With this discovery, we open the possibility for new forms of visual processing in the retina.

neuroscience↗

Dendritic calcium signals in rhesus macaque motor cortex drive an optical brain-computer interface

Calcium imaging has rapidly developed into a powerful tool for recording from large populations of neurons in vivo. Imaging in rhesus macaque motor cortex can enable the discovery of new principles of motor cortical function and can inform the design of next generation brain-computer interfaces (BCIs). Surface two-photon (2P) imaging, however, cannot presently access somatic calcium signals of neurons from all layers of macaque motor cortex due to photon scattering. Here, we demonstrate an implant and imaging system capable of chronic, motion-stabilized two-photon (2P) imaging of calcium signals from in macaques engaged in a motor task. By imaging apical dendrites, some of which originated from deep layer 5 neurons, as as well as superficial cell bodies, we achieved optical access to large populations of deep and superficial cortical neurons across dorsal premotor (PMd) and gyral primary motor (M1) cortices. Dendritic signals from individual neurons displayed tuning for different directions of arm movement, which was stable across many weeks. Combining several technical advances, we developed an optical BCI (oBCI) driven by these dendritic signals and successfully decoded movement direction online. By fusing 2P functional imaging with CLARITY volumetric imaging, we verify that an imaged dendrite, which contributed to oBCI decoding, originated from a putative Betz cell in motor cortical layer 5. This approach establishes new opportunities for studying motor control and designing BCIs.

neuroscience↗

Basal forebrain parvalbumin neurons mediate arousals from sleep induced by hypercarbia or auditory stimuli

Brief arousals from sleep in patients with sleep apnea and other disorders prevent restful sleep, and contribute to cognitive, metabolic and physiologic dysfunction. Little is currently known about which neural systems mediate these brief arousals, hindering the development of treatments. The basal forebrain (BF) receives inputs from many nuclei of the ascending arousal system. These inputs include the brainstem parabrachial neurons which promote arousal in response to elevated blood carbon dioxide levels, as seen in sleep apnea. Optical inhibition of the terminals of parabrachial neurons in the BF impairs cortical arousals to hypercarbia, but which cell types within the BF mediate cortical arousals in response to hypercarbia or other sensory stimuli is unknown. Here using optogenetic techniques in mice, we show that BF parvalbumin (PV) neurons fulfill several criteria for a system mediating brief arousals from sleep. Optical stimulation of BF PV neurons during the light period, when mice normally sleep, caused rapid transitions to wakefulness and increased wake bout durations. Unlike many other ascending arousal systems, arousals induced by stimulation of BF PV neurons were brief, resulting in only a small (13.6%) increase in the total amount of wakefulness. Bilateral optical inhibition of BF PV neurons increased the latency to arousal produced by hypercarbia or auditory stimuli. Thus, BF PV neurons are an important component of the brain circuitry which generates brief arousals from sleep in response to internal and external sensory stimuli.

neuroscience↗

How neurons move during action potentials

Neurons undergo nanometer-scale deformations during action potentials, and the underlying mechanism has been actively debated for decades. Previous observations were limited to a single spot or the cell boundary, while movement across the entire neuron during the action potential remained unclear.\n\nWe report full-field imaging of cellular deformations accompanying the action potential in mammalian neuron somas (-1.8nm~1.3nm) and neurites (-0.7nm~0.9nm), using fast quantitative phase imaging with a temporal resolution of 0.1ms and an optical pathlength sensitivity of <4pm per pixel. Spike-triggered average, synchronized to electrical recording, demonstrates that the time course of the optical phase changes matches the dynamics of the electrical signal, with the optical signal revealing the intracellular potential rather than its time derivative detected via extracellular electrodes. Using 3D cellular morphology extracted via confocal microscopy, we demonstrate that the voltage-dependent changes in the membrane tension induced by ionic repulsion can explain the magnitude, time course and spatial features of the phase imaging. Our full-field observations of the spike-induced deformations in mammalian neurons opens the door to non-invasive label-free imaging of neural signaling.

neuroscience↗

Multiple overlapping hypothalamus-brainstem circuits drive rapid threat avoidance

Animals survive environmental challenges by adapting their physiology and behavior through homeostatic regulatory processes, mediated in part by specific neuropeptide release from the hypothalamus. Animals can also avoid environmental stressors within seconds, a fast behavioral adaptation for which hypothalamic involvement is not established. Using brain-wide neural activity imaging in behaving zebrafish, here we find that hypothalamic neurons are rapidly engaged during common avoidance responses elicited by various environmental stressors. By developing methods to register cellular-resolution neural dynamics to multiplexed in situ gene expression, we find that each category of stressor recruits similar combinations of multiple peptidergic cell types in the hypothalamus. Anatomical analysis and functional manipulations demonstrate that these diverse cell types play shared roles in behavior, are glutamatergic, and converge upon spinal-projecting brainstem neurons required for avoidance. These data demonstrate that hypothalamic neural populations, classically associated with slow and specific homeostatic adaptations, also together give rise to fast and generalized avoidance behavior.

neuroscience↗

Functional maturation of human neural stem cells in a 3D bioengineered brain model enriched with fetal brain matrix

Brain extracellular matrix (ECM) is often overlooked in vitro brain tissue models, despite its instructive roles during development. Using developmental stage-sourced brain ECM in reproducible 3D bioengineered culture systems, we demonstrate enhanced functional differentiation of human induced neural stem cells (hiNSCs) into healthy neurons and astrocytes. Particularly, fetal brain tissue-derived ECM supported long-term maintenance of differentiated neurons, demonstrated by morphology, gene expression and secretome profiling. Astrocytes were evident within the second month of differentiation, and reactive astrogliosis was inhibited in brain ECM-enriched cultures when compared to unsupplemented cultures. Functional maturation of the differentiated hiNSCs within fetal ECM-enriched cultures was confirmed by calcium signaling and unsupervised cluster analysis. Additionally, the study identified native biochemical cues in decellularized ECM with notable comparisons between fetal and adult brain-derived ECMs. The development of novel brain-specific biomaterials for generating mature in vitro brain models provides an important path forward for interrogation of neuron-glia interactions.

developmental biology↗

The cortico-striatal circuit regulates sensorimotor gating via Disc1/Huntingtin-mediated Bdnf transport

Sensorimotor information processing that underlies normal cognitive and behavioral traits is dysregulated across a subset of neurological and psychiatric disorders. The cross-disease deficit in sensorimotor gating poses a unique opportunity to integrate hierarchical findings at molecular, cellular, through circuitry levels to obtain an in-depth mechanistic understanding of this process that contributes to brain physiology and pathophysiology beyond categorical segmentation of brain disorders. Based on circuitry recording with wild-type mice, we demonstrated that the cortico-striatal projection mediates sensorimotor gating responses during prepulse inhibition (PPI) task. We also found that these circuitry responses were disrupted in Disc1 locus-impairment (LI) mice, a model representing neuropsychiatric conditions. Thus, we hypothesized that Disc1-mediated molecular and cellular machinery along the cortico-striatal circuit may regulate sensorimotor gating. Anatomical and biochemical analyses of Disc1-LI mice revealed attenuated Bdnf transport along the cortico-striatal circuit. Pharmacologically augmenting Bdnf transport by chronic lithium administration, in part via Ser-421 phosphorylation of Huntingtin (Htt) and its integration into the motor machinery, restored the striatal Bdnf levels and PPI deficits in Disc1-LI mice, suggesting that the Bdnf transport attenuation mechanistically underlies the circuitry and behavioral deficits. These results also shed light on a novel mechanism and utility of lithium that is currently used as a major mood stabilizer in clinical settings. Collectively, the present study illustrates integrative biological mechanisms for sensorimotor gating, underscoring the cross-disease nature of this behavioral dimension and translational utility of the findings under the era of precision medicine in brain disorders.

neuroscience↗

Dopamine modulation of prefrontal cortex activity is manifold and operates at multiple temporal and spatial scales

While the function of dopamine in subcortical structures is largely limited to reward and movement, dopamine neurotransmission in the prefrontal cortex (PFC) is critical to a multitude of temporally and functionally diverse processes such as attention, working memory, behavioral flexibility, action selection, and stress adaptation. How does dopamine influence PFC computation of multiple temporally diverse functions? Here we find causation between sustained and burst patterns of phasic dopamine neuron activation and contemporaneous modulation of PFC neuronal activity at multiple spatio-temporal scales. These include a multidirectional and weak impact on individual PFC neuron rate activity and a robust influence on coordinated ensemble activity, gamma oscillations, and gamma-theta coupling that persisted for minutes. In addition, PFC network responses to burst pattern of dopamine firing were selectively strengthened in behaviorally active states. Thus, dopamine modulation of PFC is spatiotemporally diverse and is dictated by the pattern of dopamine neuron activation and behavioral state. These findings provide insight on the multiplex pattern of modulation by dopamine that may influence PFC computation of temporally diverse functions.

neuroscience↗