GCaMP

Last updated

GCaMP is a genetically encoded calcium indicator (GECI) initially developed in 2001 by Junichi Nakai. [1] It is a synthetic fusion of green fluorescent protein (GFP), calmodulin (CaM), and M13, a peptide sequence from myosin light-chain kinase. [2] When bound to Ca2+, GCaMP fluoresces green with a peak excitation wavelength of 480 nm and a peak emission wavelength of 510 nm. [3] It is used in biological research to measure intracellular Ca2+ levels both in vitro and in vivo using virally transfected or transgenic cell and animal lines. [2] [4] The genetic sequence encoding GCaMP can be inserted under the control of promoters exclusive to certain cell types, allowing for cell-type specific expression of GCaMP. [5] Since Ca2+ is a second messenger that contributes to many cellular mechanisms and signaling pathways, GCaMP allows researchers to quantify the activity of Ca2+-based mechanisms and study the role of Ca2+ ions in biological processes of interest.

Contents

GCaMP bound to Ca (top) and unbound (bottom) Gcamp.jpg
GCaMP bound to Ca (top) and unbound (bottom)

Structure

GCaMP consists of three key domains: an M13 domain at the N-terminus, a calmodulin (CaM) domain at the C-terminus, and a GFP domain in the center. The GFP domain is circularly permuted such that the native N- and C-termini are fused together by a six-amino-acid linking sequence, and the GFP sequence is split in the middle, creating new N- and C-termini that connect to the M13 and CaM domains. [6]

In the absence of Ca2+, the GFP chromophore is exposed to water and exists in a protonated state with minimal fluorescence intensity. Upon Ca2+ binding, the CaM domain undergoes a conformational change and tightly binds to the M13 domain alpha helix, preventing water molecules from accessing the chromophore. As a result, the chromophore rapidly deprotonates and converts into an anionic form that fluoresces brightly, similar to native GFP. [7]

History and development

In 2001, Nakai et al. reported the development of GCaMP1 as a Ca2+ probe with improved signal-to-noise ratio compared to previously developed fluorescent Ca2+ probes. [1] The first transgenic mouse expressing GCaMP1 was reported in 2004. [5] However, at 37 ˚C (physiological temperature in mammals), GCaMP1 did not fold stably or fluoresce, limiting its potential use as a calcium indicator in vivo. [1] [8]

In 2006, Tallini et al. subsequently reported the improvement of GCaMP1 to GCaMP2, which exhibited brighter fluorescence than GCaMP1 and greater stability at mammalian body temperatures. Tallini et al. expressed GCaMP2 in cardiomyocytes in mouse embryos to perform the first in vivo GCaMP imaging of Ca2+ in mammals. [8]

Further modifications of GCaMP, including GCaMP3, GCaMP5, GCaMP6, and jGCaMP7, have been developed to progressively improve the signal, sensitivity, and dynamic range of Ca2+ detection, [2] [9] [10] [11] with recent versions exhibiting fluorescence similar to native GFP. [11]

Variants in use

Both slow variants (GCaMP6s, jGCaMP7s) and fast variants (GCaMP6f, jGCaMP7f) are used in biological and neuroscience research. The slow variants are brighter and more sensitive to small changes in Ca2+ levels, such as single action potentials; on the other hand, the fast variants are less sensitive but respond more quickly, making them useful for tracking changes in Ca2+ levels over precise timescales. [12] [13] GCaMP6 also has a medium variant, GCaMP6m, whose kinetics are intermediate between GCaMP6s and GCaMP6f. [12] Other variants of jGCaMP7 are also employed: jGCaMP7b exhibits bright baseline fluorescence and is used for imaging dendrites and axons, while jGCaMP7c exhibits greater contrast between maximal and baseline fluorescence and is advantageous for imaging large populations of neurons. [12]

In 2018, Yang et al. reported the development of GCaMP-X, generated by the addition of a calmodulin-binding motif. Since the GCaMP calmodulin domain, when unbound, disrupts L-type calcium channel gating, the added calmodulin-binding motif prevents GCaMP-X from interfering with calcium-dependent signaling mechanisms. [14]

In 2020, Zhang et al. reported the development of jGCaMP8, including sensitive, medium, and fast variants, which exhibit faster kinetics and greater sensitivity than the corresponding jGCaMP7 variants. [15]

Red fluorescent indicators have also been developed: jRCaMP1a and jRCaMP1b use a circular permutation of the red fluorescent protein mRuby instead of GFP, while jRGECO1a is based on the red fluorescent protein mApple. [12] [16] Since the blue light used to excite GCaMP is scattered by tissue and the emitted green light is absorbed by blood, red fluorescent indicators provide more penetration and imaging depth in vivo than GCaMP. Use of red fluorescent indicators also avoids the photodamage caused by blue excitation light. [16] Moreover, red fluorescent indicators allow for concurrent use of optogenetics, which is difficult with GCaMP because the excitation wavelengths of GCaMP overlap with those of channelrhodopsin-2 (ChR2). [16] [17] [18] Simultaneous use of red and green GECIs can provide two-color visualization of different subcellular regions or cell populations. [16] [17] [19]

Applications in research

Neuronal activity

In neurons, action potentials induce neurotransmitter release at axon terminals by opening voltage-gated Ca2+ channels, allowing for Ca2+ influx. As a result, GCaMP is commonly used to measure increases in intracellular Ca2+ in neurons as a proxy for neuronal activity in multiple animal models, including Caenorhabditis elegans , zebrafish, Drosophila , and mice. [20] Recently, genetically encoded voltage indicators (GEVIs) have been developed alongside GECIs to more directly probe neuronal activity at the cellular level in these animal models. [21]

GCaMP has played a vital role in establishing large-scale neural recordings in animals to investigate how activity patterns in neuronal networks influence behavior. For example, Nguyen et al. (2016) used GCaMP in whole-brain imaging during free movement of C. elegans to identify neurons and groups of neurons whose activity correlated with specific locomotor behaviors. [22]

Muto et al. (2003) expressed GCaMP in zebrafish embryos to measure and map the coordinated activity of spinal motor neurons to different parts of the brain during the onset, propagation, and recovery of seizures induced by pentylenetetrazol. [23] GCaMP expression in zebrafish brains has also been used to study activation of neural circuits in cognitive processes like prey capture, impulse control, and attention. [24] [25]

Additionally, researchers have used GCaMP to observe neuronal activity in mice by expressing it under control of the Thy1 promoter, which is found in excitatory pyramidal neurons. [26] For instance, integration of neurons into circuits during motor learning has been tracked by using GCaMP to observe synchronized fluctuation patterns in Ca2+ levels. [27] [28] [29] GCaMP has also been used to observe Ca2+ dynamics in subcellular compartments of mouse neurons: Cichon and Gan (2015) used GCaMP to show that neurons in the mouse motor cortex exhibit NMDA-driven increases in Ca2+ that are independent for each dendritic spine, thus showing that individual dendritic spines regulate synaptic plasticity. [30] Finally, GCaMP has been used to identify activity patterns in specific regions of the mouse brain. For instance, Jones et al. (2018) used GCaMP6 in mice to measure neuronal activity in the suprachiasmatic nucleus (SCN), the mammalian circadian pacemaker, and showed that SCN neurons that produced vasoactive intestinal peptide (VIP) exhibited daily activity rhythms in vivo that correlated with VIP release. [31]

GCaMP has also been combined with fiber photometry to measure population-level Ca2+ changes within subpopulations of neurons in freely moving animals. [32] For instance, Clarkson et al. (2017) used this method to show that neurons in the arcuate nucleus of the hypothalamus synchronize to increases in Ca2+ immediately prior to pulses of luteinizing hormone (LH). [33] While GCaMP imaging with fiber photometry cannot track changes in Ca2+ levels within individual neurons, it provides greater temporal resolution for large-scale changes. [34]

Cardiac conduction

Ca2+ currents through cardiomyocyte gap junctions mediate synchronized contraction of cardiac tissue. As a result, GCaMP expression in cardiomyocytes, both in vitro and in vivo, has been used to study Ca2+-influx-dependent excitation and contraction in zebrafish and mice. [35] For instance, Tallini et al. (2006) expressed GCaMP2 in mouse embryos to show that, at embryonic day 10.5, electrical conduction was rapid in the atria and ventricles but slow in the atrioventricular canal. [8] Chi et al. (2008) used a transgenic cardiac-specific GCaMP zebrafish line to image cardiomyocyte activation throughout the cardiac cycle; from their results, they characterized four developmental stages of the zebrafish cardiac conduction system and identified 17 novel mutations affecting cardiac conduction. [36] However, uncontrolled expression of GCaMP leads to cardiac hypertrophy due to overexpression of the calmodulin motif, which interferes with intracellular calcium signaling. As a result, experiments using cardiac tissue should carefully control the level of GCaMP expression. [8]

Signaling pathway activation

Since Ca2+ is a common second messenger, GCaMP has been used to monitor the activation of signaling pathways. For instance, Bonder and McCarthy (2014) used GCaMP to show that astrocytic G-protein coupled receptor (GPCR) signaling and subsequent Ca2+ release was not responsible for neurovascular coupling, the process by which changes in neuronal activity lead to changes in local blood flow. [37] Similarly, Greer and Bear et al. (2016) used GCaMP to characterize the dynamics of Ca2+ influx in necklace olfactory neuron signaling, which uses transmembrane MS4A proteins as chemoreceptors. [38]

See also

Related Research Articles

<span class="mw-page-title-main">Green fluorescent protein</span> Protein that exhibits bright green fluorescence when exposed to ultraviolet light

The green fluorescent protein (GFP) is a protein that exhibits green fluorescence when exposed to light in the blue to ultraviolet range. The label GFP traditionally refers to the protein first isolated from the jellyfish Aequorea victoria and is sometimes called avGFP. However, GFPs have been found in other organisms including corals, sea anemones, zoanithids, copepods and lancelets.

<span class="mw-page-title-main">Behavioral neuroscience</span> Field of study

Behavioral neuroscience, also known as biological psychology, biopsychology, or psychobiology, is the application of the principles of biology to the study of physiological, genetic, and developmental mechanisms of behavior in humans and other animals.

Channelrhodopsins are a subfamily of retinylidene proteins (rhodopsins) that function as light-gated ion channels. They serve as sensory photoreceptors in unicellular green algae, controlling phototaxis: movement in response to light. Expressed in cells of other organisms, they enable light to control electrical excitability, intracellular acidity, calcium influx, and other cellular processes. Channelrhodopsin-1 (ChR1) and Channelrhodopsin-2 (ChR2) from the model organism Chlamydomonas reinhardtii are the first discovered channelrhodopsins. Variants that are sensitive to different colors of light or selective for specific ions have been cloned from other species of algae and protists.

<span class="mw-page-title-main">Calcium signaling</span> Intracellular communication process

Calcium signaling is the use of calcium ions (Ca2+) to communicate and drive intracellular processes often as a step in signal transduction. Ca2+ is important for cellular signalling, for once it enters the cytosol of the cytoplasm it exerts allosteric regulatory effects on many enzymes and proteins. Ca2+ can act in signal transduction resulting from activation of ion channels or as a second messenger caused by indirect signal transduction pathways such as G protein-coupled receptors.

Cameleon is an engineered protein based on variant of green fluorescent protein used to visualize calcium levels in living cells. It is a genetically encoded calcium sensor created by Roger Y. Tsien and coworkers. The name is a conflation of CaM (the common abbreviation of calmodulin) and chameleon to indicate the fact that the sensor protein undergoes a conformation change and radiates at an altered wavelength upon calcium binding to the calmodulin element of the Cameleon. Cameleon was the first genetically encoded calcium sensor that could be used for ratiometric measurements and the first to be used in a transgenic animal to record activity in neurons and muscle cells. Cameleon and other genetically encoded calcium indicators (GECIs) have found many applications in neuroscience and other fields of biology, including understanding the mechanisms of cell signaling by conducting time-resolved Ca2+ activity measurement experiments with endoplasmic reticulum (ER) enzymes. It was created by fusing BFP, calmodulin, calmodulin-binding peptide M13 and EGFP.

<span class="mw-page-title-main">SK channel</span> Protein subfamily of calcium-activated potassium channels

SK channels are a subfamily of calcium-activated potassium channels. They are so called because of their small single channel conductance in the order of 10 pS. SK channels are a type of ion channel allowing potassium cations to cross the cell membrane and are activated (opened) by an increase in the concentration of intracellular calcium through N-type calcium channels. Their activation limits the firing frequency of action potentials and is important for regulating afterhyperpolarization in the neurons of the central nervous system as well as many other types of electrically excitable cells. This is accomplished through the hyperpolarizing leak of positively charged potassium ions along their concentration gradient into the extracellular space. This hyperpolarization causes the membrane potential to become more negative. SK channels are thought to be involved in synaptic plasticity and therefore play important roles in learning and memory.

<span class="mw-page-title-main">GAL4/UAS system</span> Biochemical method

The GAL4-UAS system is a biochemical method used to study gene expression and function in organisms such as the fruit fly. It is based on the finding by Hitoshi Kakidani and Mark Ptashne, and Nicholas Webster and Pierre Chambon in 1988 that Gal4 binding to UAS sequences activates gene expression. The method was introduced into flies by Andrea Brand and Norbert Perrimon in 1993 and is considered a powerful technique for studying the expression of genes. The system has two parts: the Gal4 gene, encoding the yeast transcription activator protein Gal4, and the UAS, an enhancer to which GAL4 specifically binds to activate gene transcription.

<span class="mw-page-title-main">Brainbow</span> Neuroimaging technique to differentiate neurons

Brainbow is a process by which individual neurons in the brain can be distinguished from neighboring neurons using fluorescent proteins. By randomly expressing different ratios of red, green, and blue derivatives of green fluorescent protein in individual neurons, it is possible to flag each neuron with a distinctive color. This process has been a major contribution to the field of neural connectomics.

<span class="mw-page-title-main">CAMK4</span> Protein-coding gene in the species Homo sapiens

Calcium/calmodulin-dependent protein kinase type IV is an enzyme that in humans is encoded by the CAMK4 gene.

Calcium concentration microdomains (CCMs) are sites in a cell's cytoplasm with a localised high calcium ion (Ca2+) concentration. They are found immediately around the intracellular opening of calcium channels; when a calcium channel opens, the Ca2+ concentration in the adjacent CCM increases up to several hundred micromolar (μM). These microdomains take part in calcium signaling, which has a diverse range of potential outcomes.

<span class="mw-page-title-main">CAMK1</span> Protein-coding gene in the species Homo sapiens

Calcium/calmodulin-dependent protein kinase type 1 is an enzyme that in humans is encoded by the CAMK1 gene.

<span class="mw-page-title-main">Visinin-like protein 1</span> Protein-coding gene in the species Homo sapiens

Visinin-like protein 1 is a protein that in humans is encoded by the VSNL1 gene.

<span class="mw-page-title-main">CAMKK2</span> Protein-coding gene in humans

Calcium/calmodulin-dependent protein kinase kinase 2 is an enzyme that in humans is encoded by the CAMKK2 gene.

<span class="mw-page-title-main">KCNN2</span> Protein-coding gene in the species Homo sapiens

Potassium intermediate/small conductance calcium-activated channel, subfamily N, member 2, also known as KCNN2, is a protein which in humans is encoded by the KCNN2 gene. KCNN2 is an ion channel protein also known as KCa2.2.

Optogenetics is a biological technique to control the activity of neurons or other cell types with light. This is achieved by expression of light-sensitive ion channels, pumps or enzymes specifically in the target cells. On the level of individual cells, light-activated enzymes and transcription factors allow precise control of biochemical signaling pathways. In systems neuroscience, the ability to control the activity of a genetically defined set of neurons has been used to understand their contribution to decision making, learning, fear memory, mating, addiction, feeding, and locomotion. In a first medical application of optogenetic technology, vision was partially restored in a blind patient with Retinitis pigmentosa.

Calcium imaging is a microscopy technique to optically measure the calcium (Ca2+) status of an isolated cell, tissue or medium. Calcium imaging takes advantage of calcium indicators, fluorescent molecules that respond to the binding of Ca2+ ions by fluorescence properties. Two main classes of calcium indicators exist: chemical indicators and genetically encoded calcium indicators (GECI). This technique has allowed studies of calcium signalling in a wide variety of cell types. In neurons, action potential generation is always accompanied by rapid influx of Ca2+ ions. Thus, calcium imaging can be used to monitor the electrical activity in hundreds of neurons in cell culture or in living animals, which has made it possible to observe the activity of neuronal circuits during ongoing behavior.

Genetically encoded voltage indicator is a protein that can sense membrane potential in a cell and relate the change in voltage to a form of output, often fluorescent level. It is a promising optogenetic recording tool that enables exporting electrophysiological signals from cultured cells, live animals, and ultimately human brain. Examples of notable GEVIs include ArcLight, ASAP1, ASAP3, Archons, SomArchon, and Ace2N-mNeon.

<span class="mw-page-title-main">William Schafer</span> American geneticist

William Ronald Schafer is a neuroscientist and geneticist who has made important contributions to understanding the molecular and neural basis of behaviour. His work, principally in the nematode C. elegans, has used an interdisciplinary approach to investigate how small groups of neurons generate behavior, and he has pioneered methodological approaches, including optogenetic neuroimaging and automated behavioural phenotyping, that have been widely influential in the broader neuroscience field. He has made significant discoveries on the functional properties of ionotropic receptors in sensory transduction and on the roles of gap junctions and extrasynaptic modulation in neuronal microcircuits. More recently, he has applied theoretical ideas from network science and control theory to investigate the structure and function of simple neuronal connectomes, with the goal of understanding conserved computational principles in larger brains. He is an EMBO member, Welcome Investigator and Fellow of the Academy of Medical Sciences.

Fiber photometry is a calcium imaging technique that captures 'bulk' or population-level calcium (Ca2+) activity from specific cell-types within a brain region or functional network in order to study neural circuits Population-level calcium activity can be correlated with behavioral tasks, such as spatial learning, memory recall and goal-directed behaviors. The technique involves the surgical implantation of fiber optics into the brains of living animals. The benefits to researchers are that optical fibers are simpler to implant, less invasive and less expensive than other calcium methods, and there is less weight and stress on the animal, as compared to miniscopes. It also allows for imaging of multiple interacting brain regions and integration with other neuroscience techniques. The limitations of fiber photometry are low cellular and spatial resolution, and the fact that animals must be securely tethered to a rigid fiber bundle, which may impact the naturalistic behavior of smaller mammals such as mice.

Optogenetics began with methods to alter neuronal activity with light, using e.g. channelrhodopsins. In a broader sense, optogenetic approaches also include the use of genetically encoded biosensors to monitor the activity of neurons or other cell types by measuring fluorescence or bioluminescence. Genetically encoded calcium indicators (GECIs) are used frequently to monitor neuronal activity, but other cellular parameters such as membrane voltage or second messenger activity can also be recorded optically. The use of optogenetic sensors is not restricted to neuroscience, but plays increasingly important roles in immunology, cardiology and cancer research.

References

  1. 1 2 3 Nakai J, Ohkura M, Imoto K (February 2001). "A high signal-to-noise Ca(2+) probe composed of a single green fluorescent protein". Nature Biotechnology. 19 (2): 137–41. doi:10.1038/84397. PMID   11175727. S2CID   30254550.
  2. 1 2 3 Chen TW, Wardill TJ, Sun Y, Pulver SR, Renninger SL, Baohan A, et al. (July 2013). "Ultrasensitive fluorescent proteins for imaging neuronal activity". Nature. 499 (7458): 295–300. Bibcode:2013Natur.499..295C. doi:10.1038/nature12354. PMC   3777791 . PMID   23868258.
  3. ↑ Barnett LM, Hughes TE, Drobizhev M (2017-02-09). "Deciphering the molecular mechanism responsible for GCaMP6m's Ca2+-dependent change in fluorescence". PLOS ONE. 12 (2): e0170934. Bibcode:2017PLoSO..1270934B. doi: 10.1371/journal.pone.0170934 . PMC   5300113 . PMID   28182677.
  4. ↑ Whitaker M (2010-01-01). "Genetically encoded probes for measurement of intracellular calcium". Calcium in Living Cells. Methods in Cell Biology. Vol. 99. pp. 153–82. doi:10.1016/B978-0-12-374841-6.00006-2. ISBN   9780123748416. PMC   3292878 . PMID   21035686.
  5. 1 2 Ji G, Feldman ME, Deng KY, Greene KS, Wilson J, Lee JC, et al. (May 2004). "Ca2+-sensing transgenic mice: postsynaptic signaling in smooth muscle". The Journal of Biological Chemistry. 279 (20): 21461–8. doi:10.1074/jbc.M401084200. PMID   14990564. S2CID   9532711.
  6. ↑ Akerboom J, Rivera JD, Guilbe MM, Malavé EC, Hernandez HH, Tian L, et al. (March 2009). "Crystal structures of the GCaMP calcium sensor reveal the mechanism of fluorescence signal change and aid rational design". The Journal of Biological Chemistry. 284 (10): 6455–64. doi: 10.1074/jbc.M807657200 . PMC   2649101 . PMID   19098007.
  7. ↑ Wang Q, Shui B, Kotlikoff MI, Sondermann H (December 2008). "Structural basis for calcium sensing by GCaMP2". Structure. 16 (12): 1817–27. doi:10.1016/j.str.2008.10.008. PMC   2614139 . PMID   19081058.
  8. 1 2 3 4 Tallini YN, Ohkura M, Choi BR, Ji G, Imoto K, Doran R, et al. (March 2006). "Imaging cellular signals in the heart in vivo: Cardiac expression of the high-signal Ca2+ indicator GCaMP2". Proceedings of the National Academy of Sciences of the United States of America. 103 (12): 4753–8. Bibcode:2006PNAS..103.4753T. doi: 10.1073/pnas.0509378103 . PMC   1450242 . PMID   16537386.
  9. ↑ Tian L, Hires SA, Mao T, Huber D, Chiappe ME, Chalasani SH, et al. (December 2009). "Imaging neural activity in worms, flies and mice with improved GCaMP calcium indicators". Nature Methods. 6 (12): 875–81. doi:10.1038/nmeth.1398. PMC   2858873 . PMID   19898485.
  10. ↑ Akerboom J, Chen TW, Wardill TJ, Tian L, Marvin JS, Mutlu S, et al. (October 2012). "Optimization of a GCaMP calcium indicator for neural activity imaging". The Journal of Neuroscience. 32 (40): 13819–40. doi:10.1523/JNEUROSCI.2601-12.2012. PMC   3482105 . PMID   23035093.
  11. 1 2 Inoue M (June 2020). "Genetically encoded calcium indicators to probe complex brain circuit dynamics in vivo". Neuroscience Research. 169: 2–8. doi:10.1016/j.neures.2020.05.013. PMID   32531233. S2CID   219559849.
  12. 1 2 3 4 Haery L. "Switch to GECO? An Overview of AAV Encoded Calcium Sensors". blog.addgene.org. Retrieved 2021-05-06.
  13. ↑ Bassett JJ, Monteith GR (2017-01-01). "Genetically Encoded Calcium Indicators as Probes to Assess the Role of Calcium Channels in Disease and for High-Throughput Drug Discovery". Ion Channels Down Under (PDF). Advances in Pharmacology. Vol. 79. pp. 141–171. doi:10.1016/bs.apha.2017.01.001. ISBN   9780128104132. PMID   28528667.
  14. ↑ Yang Y, Liu N, He Y, Liu Y, Ge L, Zou L, et al. (April 2018). "Improved calcium sensor GCaMP-X overcomes the calcium channel perturbations induced by the calmodulin in GCaMP". Nature Communications. 9 (1): 1504. Bibcode:2018NatCo...9.1504Y. doi:10.1038/s41467-018-03719-6. PMC   5904127 . PMID   29666364.
  15. ↑ Zhang Y, Rózsa M, Bushey D, Reep D, Broussard GY, Tsang A, et al. (2020). "jGCaMP8 Fast Genetically Encoded Calcium Indicators": 361685 Bytes. doi:10.25378/janelia.13148243.v4.{{cite journal}}: Cite journal requires |journal= (help)
  16. 1 2 3 4 Dana H, Mohar B, Sun Y, Narayan S, Gordus A, Hasseman JP, et al. (March 2016). Häusser M (ed.). "Sensitive red protein calcium indicators for imaging neural activity". eLife. 5: e12727. doi: 10.7554/eLife.12727 . PMC   4846379 . PMID   27011354.
  17. 1 2 Akerboom J, Carreras Calderón N, Tian L, Wabnig S, Prigge M, Tolö J, et al. (2013). "Genetically encoded calcium indicators for multi-color neural activity imaging and combination with optogenetics". Frontiers in Molecular Neuroscience. 6: 2. doi: 10.3389/fnmol.2013.00002 . PMC   3586699 . PMID   23459413.
  18. ↑ Patriarchi, Tommaso; Mohebi, Ali; Sun, Junqing; Marley, Aaron; Liang, Ruqiang; Dong, Chunyang; Puhger, Kyle; Mizuno, Grace Or; Davis, Carolyn M.; Wiltgen, Brian; von Zastrow, Mark; Berke, Joshua D.; Tian, Lin (2020-09-07). "An expanded palette of dopamine sensors for multiplex imaging in vivo". Nature Methods. 17 (11): 1147–1155. doi:10.1038/s41592-020-0936-3. ISSN   1548-7105.
  19. ↑ Zhao Y, Araki S, Wu J, Teramoto T, Chang YF, Nakano M, et al. (September 2011). "An expanded palette of genetically encoded Ca²⁺ indicators". Science. 333 (6051): 1888–91. doi:10.1126/science.1208592. PMC   3560286 . PMID   21903779.
  20. ↑ Dana H, Sun Y, Mohar B, Hulse BK, Kerlin AM, Hasseman JP, et al. (July 2019). "High-performance calcium sensors for imaging activity in neuronal populations and microcompartments". Nature Methods. 16 (7): 649–657. doi:10.1038/s41592-019-0435-6. PMID   31209382. S2CID   189927684.
  21. ↑ Yang, Helen H.; St-Pierre, François (2016-09-28). "Genetically Encoded Voltage Indicators: Opportunities and Challenges". Journal of Neuroscience. 36 (39): 9977–9989. doi:10.1523/JNEUROSCI.1095-16.2016. ISSN   0270-6474. PMC   5039263 . PMID   27683896.
  22. ↑ Nguyen JP, Shipley FB, Linder AN, Plummer GS, Liu M, Setru SU, et al. (February 2016). "Whole-brain calcium imaging with cellular resolution in freely behaving Caenorhabditis elegans". Proceedings of the National Academy of Sciences of the United States of America. 113 (8): E1074-81. arXiv: 1501.03463 . Bibcode:2016PNAS..113E1074N. doi: 10.1073/pnas.1507110112 . PMC   4776509 . PMID   26712014.
  23. ↑ Muto A, Ohkura M, Kotani T, Higashijima S, Nakai J, Kawakami K (March 2011). "Genetic visualization with an improved GCaMP calcium indicator reveals spatiotemporal activation of the spinal motor neurons in zebrafish". Proceedings of the National Academy of Sciences of the United States of America. 108 (13): 5425–30. Bibcode:2011PNAS..108.5425M. doi: 10.1073/pnas.1000887108 . PMC   3069178 . PMID   21383146.
  24. ↑ Muto A, Kawakami K (2013). "Prey capture in zebrafish larvae serves as a model to study cognitive functions". Frontiers in Neural Circuits. 7: 110. doi: 10.3389/fncir.2013.00110 . PMC   3678101 . PMID   23781176.
  25. ↑ Parker MO, Brock AJ, Walton RT, Brennan CH (2013). "The role of zebrafish (Danio rerio) in dissecting the genetics and neural circuits of executive function". Frontiers in Neural Circuits. 7: 63. doi: 10.3389/fncir.2013.00063 . PMC   3619107 . PMID   23580329.
  26. ↑ Chen Q, Cichon J, Wang W, Qiu L, Lee SJ, Campbell NR, et al. (October 2012). "Imaging neural activity using Thy1-GCaMP transgenic mice". Neuron. 76 (2): 297–308. doi:10.1016/j.neuron.2012.07.011. PMC   4059513 . PMID   23083733.
  27. ↑ Peters AJ, Chen SX, Komiyama T (June 2014). "Emergence of reproducible spatiotemporal activity during motor learning". Nature. 510 (7504): 263–7. Bibcode:2014Natur.510..263P. doi:10.1038/nature13235. PMID   24805237. S2CID   4463927.
  28. ↑ Ziv Y, Burns LD, Cocker ED, Hamel EO, Ghosh KK, Kitch LJ, et al. (March 2013). "Long-term dynamics of CA1 hippocampal place codes". Nature Neuroscience. 16 (3): 264–6. doi:10.1038/nn.3329. PMC   3784308 . PMID   23396101.
  29. ↑ Lin MZ, Schnitzer MJ (August 2016). "Genetically encoded indicators of neuronal activity". Nature Neuroscience. 19 (9): 1142–53. doi:10.1038/nn.4359. PMC   5557009 . PMID   27571193.
  30. ↑ Cichon J, Gan WB (April 2015). "Branch-specific dendritic Ca(2+) spikes cause persistent synaptic plasticity". Nature. 520 (7546): 180–5. Bibcode:2015Natur.520..180C. doi:10.1038/nature14251. PMC   4476301 . PMID   25822789.
  31. ↑ Jones JR, Simon T, Lones L, Herzog ED (September 2018). "SCN VIP Neurons Are Essential for Normal Light-Mediated Resetting of the Circadian System". The Journal of Neuroscience. 38 (37): 7986–7995. doi:10.1523/JNEUROSCI.1322-18.2018. PMC   6596148 . PMID   30082421.
  32. ↑ Han SY, Clarkson J, Piet R, Herbison AE (November 2018). "Optical Approaches for Interrogating Neural Circuits Controlling Hormone Secretion". Endocrinology. 159 (11): 3822–3833. doi: 10.1210/en.2018-00594 . PMID   30304401. S2CID   52954832.
  33. ↑ Clarkson J, Han SY, Piet R, McLennan T, Kane GM, Ng J, et al. (November 2017). "Definition of the hypothalamic GnRH pulse generator in mice". Proceedings of the National Academy of Sciences of the United States of America. 114 (47): E10216–E10223. Bibcode:2017PNAS..11410216C. doi: 10.1073/pnas.1713897114 . PMC   5703322 . PMID   29109258.
  34. ↑ Gunaydin LA, Grosenick L, Finkelstein JC, Kauvar IV, Fenno LE, Adhikari A, et al. (June 2014). "Natural neural projection dynamics underlying social behavior". Cell. 157 (7): 1535–51. doi:10.1016/j.cell.2014.05.017. PMC   4123133 . PMID   24949967.
  35. ↑ Kaestner L, Scholz A, Tian Q, Ruppenthal S, Tabellion W, Wiesen K, et al. (May 2014). "Genetically encoded Ca2+ indicators in cardiac myocytes". Circulation Research. 114 (10): 1623–39. doi: 10.1161/CIRCRESAHA.114.303475 . PMID   24812351. S2CID   10856784.
  36. ↑ Chi NC, Shaw RM, Jungblut B, Huisken J, Ferrer T, Arnaout R, et al. (May 2008). "Genetic and physiologic dissection of the vertebrate cardiac conduction system". PLOS Biology. 6 (5): e109. doi: 10.1371/journal.pbio.0060109 . PMC   2430899 . PMID   18479184.
  37. ↑ Bonder DE, McCarthy KD (September 2014). "Astrocytic Gq-GPCR-linked IP3R-dependent Ca2+ signaling does not mediate neurovascular coupling in mouse visual cortex in vivo". The Journal of Neuroscience. 34 (39): 13139–50. doi:10.1523/JNEUROSCI.2591-14.2014. PMC   4172806 . PMID   25253859.
  38. ↑ Greer PL, Bear DM, Lassance JM, Bloom ML, Tsukahara T, Pashkovski SL, et al. (June 2016). "A Family of non-GPCR Chemosensors Defines an Alternative Logic for Mammalian Olfaction". Cell. 165 (7): 1734–1748. doi:10.1016/j.cell.2016.05.001. PMC   4912422 . PMID   27238024.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.