Peripheral Ca2.2 Channels in the Skin Regulate Prolonged Heat Hypersensitivity during Neuroinflammation.

Neuroinflammation can lead to chronic maladaptive pain affecting millions of people worldwide. Neurotransmitters, cytokines, and ion channels are implicated in neuroimmune cell signaling, but their roles in specific behavioral responses are not fully elucidated. Voltage-gated Ca2.

Peripheral Ca2.2 channels in skin regulate prolonged heat hypersensitivity during neuroinflammation.

Neuroinflammation can lead to chronic maladaptive pain affecting millions of people worldwide. Neurotransmitters, cytokines, and ion channels are implicated in neuro-immune cell signaling but their roles in specific behavioral responses are not fully elucidated. Voltage-gated Ca2.

Interleukin-1α links peripheral Ca2.2 channel activation to rapid adaptive increases in heat sensitivity in skin.

Neurons have the unique capacity to adapt output in response to changes in their environment. Within seconds, sensory nerve endings can become hypersensitive to stimuli in response to potentially damaging events. The underlying behavioral response is well studied, but several of the key signaling molecules that mediate sensory hypersensitivity remain unknown.

Interleukin-1α links peripheral Ca2.2 channel activation to rapid adaptive increases in heat sensitivity in skin.

Neurons have the unique capacity to adapt output in response to changes in their environment. Within seconds, sensory nerve endings can become hypersensitive to stimuli in response to potentially damaging events. The underlying behavioral response is well studied, but several of the key signaling molecules that mediate sensory hypersensitivity remain unknown.

Engineering luminopsins with improved coupling efficiencies.

Significance: Luminopsins (LMOs) are bioluminescent-optogenetic tools with a luciferase fused to an opsin that allow bimodal control of neurons by providing both optogenetic and chemogenetic access. Determining which design features contribute to the efficacy of LMOs will be beneficial for further improving LMOs for use in research.

Aim: We investigated the relative impact of luciferase brightness, opsin sensitivity, pairing of emission and absorption wavelength, and arrangement of moieties on the function of LMOs.

Efficient opto- and chemogenetic control in a single molecule driven by FRET-modified bioluminescence.

Significance: Bioluminescent optogenetics (BL-OG) offers a unique and powerful approach to manipulate neural activity both opto- and chemogenetically using a single actuator molecule (a LuMinOpsin, LMO).

Aim: To further enhance the utility of BL-OG by improving the efficacy of chemogenetic (bioluminescence-driven) LMO activation.

Approach: We developed novel luciferases optimized for Förster resonance energy transfer when fused to the fluorescent protein mNeonGreen, generating bright bioluminescent (BL) emitters spectrally tuned to Channelrhodopsin 1 (VChR1).

Engineering luminopsins with improved coupling efficiencies.

Significance: Luminopsins (LMOs) are bioluminescent-optogenetic tools with a luciferase fused to an opsin that allow bimodal control of neurons by providing both optogenetic and chemogenetic access. Determining which design features contribute to the efficacy of LMOs will be beneficial for further improving LMOs for use in research.

Aim: We investigated the relative impact of luciferase brightness, opsin sensitivity, pairing of emission and absorption wavelength, and arrangement of moieties on the function of LMOs.

ω-Phonetoxins inhibit voltage-gated calcium Ca2.2 ion channel splice isoforms of dorsal root ganglia.

Cell-specific alternative splicing of pre-mRNA generates functionally distinct voltage-gated Ca2.2 channels. Ca2.

A Bioluminescent Activity Dependent (BLADe) Platform for Converting Neuronal Activity to Photoreceptor Activation.

We developed a platform that utilizes a calcium-dependent luciferase to convert neuronal activity into activation of light sensing domains within the same cell. The platform is based on a luciferase variant with high light emission split by calmodulin-M13 sequences that depends on influx of calcium ions (Ca) for functional reconstitution. In the presence of its luciferin, coelenterazine (CTZ), Ca influx results in light emission that drives activation of photoreceptors, including optogenetic channels and LOV domains.

A New Highly Efficient Molecule for Both Optogenetic and Chemogenetic Control Driven by FRET Amplification of BioLuminescence.

Significance: Bioluminescent optogenetics (BL-OG) offers a unique and powerful approach to manipulate neural activity both opto- and chemogenetically using a single actuator molecule (a LuMinOpsin, LMO).

Aim: To further enhance the utility of BL-OG by improving the efficacy of chemogenetic (bioluminescence-driven) LMO activation.

Approach: We developed novel luciferases optimized for Forster resonance energy transfer (FRET) when fused to the fluorescent protein mNeonGreen, generating bright bioluminescent (BL) emitters spectrally tuned to Volvox Channelrhodopsin 1 (VChR1).

CaBLAM! A high-contrast bioluminescent Ca indicator derived from an engineered luciferase.

Ca plays many critical roles in cell physiology and biochemistry, leading researchers to develop a number of fluorescent small molecule dyes and genetically encodable probes that optically report changes in Ca concentrations in living cells. Though such fluorescence-based genetically encoded Ca indicators (GECIs) have become a mainstay of modern Ca sensing and imaging, bioluminescence-based GECIs-probes that generate light through oxidation of a small-molecule by a luciferase or photoprotein-have several distinct advantages over their fluorescent counterparts. Bioluminescent tags do not photobleach, do not suffer from nonspecific autofluorescent background, and do not lead to phototoxicity since they do not require the extremely bright extrinsic excitation light typically required for fluorescence imaging, especially with 2-photon microscopy.

Up-regulation of cholesterol synthesis pathways and limited neurodegeneration in a knock-in mutant mouse model of ALS.

Unlabelled: Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disorder affecting brain and spinal cord motor neurons. Mutations in the copper/zinc superoxide dismutase gene ( ) are associated with ∼20% of inherited and 1-2% of sporadic ALS cases. Much has been learned from mice expressing transgenic copies of mutant SOD1, which typically involve high-level transgene expression, thereby differing from ALS patients expressing one mutant gene copy.

Selective control of synaptically-connected circuit elements by all-optical synapses.

Understanding percepts, engrams and actions requires methods for selectively modulating synaptic communication between specific subsets of interconnected cells. Here, we develop an approach to control synaptically connected elements using bioluminescent light: Luciferase-generated light, originating from a presynaptic axon terminal, modulates an opsin in its postsynaptic target. Vesicular-localized luciferase is released into the synaptic cleft in response to presynaptic activity, creating a real-time Optical Synapse.

Analysing an allelic series of rare missense variants of CACNA1I in a Swedish schizophrenia cohort.

CACNA1I is implicated in the susceptibility to schizophrenia by large-scale genetic association studies of single nucleotide polymorphisms. However, the channelopathy of CACNA1I in schizophrenia is unknown. CACNA1I encodes CaV3.

Heat But Not Mechanical Hypersensitivity Depends on Voltage-Gated Ca2.2 Calcium Channel Activity in Peripheral Axon Terminals Innervating Skin.

Voltage-gated Ca2.2 calcium channels are expressed in nociceptors at presynaptic terminals, soma, and axons. Ca2.

Bioluminescent optogenetic (BL-OG) activation of neurons during mouse postnatal brain development.

Bioluminescent optogenetics (BL-OG) allows activation of photosensory proteins, such as opsins, by either fiberoptics or by administering a luciferin. BL-OG thus confers both optogenetic and chemogenetic access within the same genetically targeted neuron. This bimodality offers a powerful approach for non-invasive chemogenetic manipulation of neural activity during brain development and adult behaviors with standard optogenetic spatiotemporal precision.

Epigenetic control of ion channel expression and cell-specific splicing in nociceptors: Chronic pain mechanisms and potential therapeutic targets.

Ion channels underlie all forms for electrical signaling including the transmission of information about harmful events. Voltage-gated calcium ion channels have dual function, they support electrical signaling as well as intracellular calcium signaling through excitation-dependent calcium entry across the plasma membrane. Mechanisms that regulate ion channel forms and actions are essential for myriad cell functions and these are targeted by drugs and therapeutics.

Miniaturized Devices for Bioluminescence Imaging in Freely Behaving Animals.

In vivo fluorescence miniature microscopy has recently proven a major advance, enabling cellular imaging in freely behaving animals. However, fluorescence imaging suffers from autofluorescence, phototoxicity, photobleaching and non- homogeneous illumination artifacts. These factors limit the quality and time course of data collection.

Cell-specific exon methylation and CTCF binding in neurons regulate calcium ion channel splicing and function.

Cell-specific alternative splicing modulates myriad cell functions and is disrupted in disease. The mechanisms governing alternative splicing are known for relatively few genes and typically focus on RNA splicing factors. In sensory neurons, cell-specific alternative splicing of the presynaptic Ca channel gene modulates opioid sensitivity.

Framework for advancing rigorous research.

There is a pressing need to increase the rigor of research in the life and biomedical sciences. To address this issue, we propose that communities of 'rigor champions' be established to campaign for reforms of the research culture that has led to shortcomings in rigor. These communities of rigor champions would also assist in the development and adoption of a comprehensive educational platform that would teach the principles of rigorous science to researchers at all career stages.

Cacna1b alternative splicing impacts excitatory neurotransmission and is linked to behavioral responses to aversive stimuli.

Presynaptic Ca2.2 channels control calcium entry that triggers neurotransmitter release at both central and peripheral synapses. The Cacna1b gene encodes the α1-pore forming subunit of Ca2.

Alternative splicing of neuronal genes: new mechanisms and new therapies.

Dynamic changes in alternative splicing during the life cycle of neurons support development and plasticity, and are implicated in disease pathology. Cell-specific alternative splicing programs coordinate exon selection across networks of functionally connected genes. In this opinion piece, we highlight recent publications that identify some of the molecular mechanisms-RNA and DNA binding proteins and epigenetic modifications-which direct cell-specific exon selection during pre-mRNA splicing.

Circuit Dysfunction in Model First Detected in Sensory Feedback Prior to Motor Neuron Degeneration Is Alleviated by BMP Signaling.

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease for which the origin and underlying cellular defects are not fully understood. Although motor neuron degeneration is the signature feature of ALS, it is not clear whether motor neurons or other cells of the motor circuit are the site of disease initiation. To better understand the contribution of multiple cell types in ALS, we made use of a knock-in model, in which all cells harbor the disease allele.

Meta-analysis of Genetic Modifiers Reveals Candidate Dysregulated Pathways in Amyotrophic Lateral Sclerosis.

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease that has significant overlap with frontotemporal dementia (FTD). Mutations in specific genes have been identified that can cause and/or predispose patients to ALS. However, the clinical variability seen in ALS patients suggests that additional genes impact pathology, susceptibility, severity, and/or progression of the disease.