The spatiotemporal limits of developmental Erk signalling
Johnson, H. E., Goyal, Y., Pannucci, N. L., Schüpbach, T., Shvartsman, S. Y., & Toettcher, J. E.
A recently published paper in Developmental Cell by Johnson, Goyal et al. assessed the spatial and temporal role of Erk signalling in Drosophila embryo development. Using an optogenetic tool to control Erk activity in vivo with Mightex’s Polygon400 Patterned Illuminator, the authors investigated the developmental role of Erk signalling in different areas of the embryo by delivering precise strips of illumination. Johnson, Goyal et al. showed that optogenetic stimulation of Erk signalling the middle, but not the tail ends, of the embryo disrupted proper development and that changes were localized to the area of stimulation. In addition, the authors found that optogenetic stimulation of Erk signalling in the entire embryo appeared most lethal in the early stages of development (0-4h), compared to the later stages (4-24h). This paper demonstrates the significant spatial and temporal role of Erk signalling in early development, as well as how this novel optogenetic tool can be used with Mightex’s Polygon400 to obtain fine spatial control of Erk signalling in vivo.Johnson, H. E., Goyal, Y., Pannucci, N. L., Schüpbach, T., Shvartsman, S. Y., & Toettcher, J. E., "The Spatiotemporal Limits of Developmental Erk Signaling", Developmental Cell, published 23 January 2017.
Optogenetic Manipulation of Anatomical Re-Entry by Light-Guide Generation of a Reversible Local Conduction Block
Watanabe, Masaya, Iolanda Feola, Rupamanjari Majumder, Wanchana Jangsangthong, Alexander S. Teplenin, Dirk L. Ypey, Martin J. Schalij, Katja Zeppenfeld, Antoine AF de Vries, & Daniël A. Pijnappels.
A recently published paper in Cardiovascular Research by Watanabe et al. investigated optogenetic termination of anatomical re-entry, a type of tachycardia. Cardiac tissue cells were transfected with Ca2+-translocating channelrhodopsin (CatCh) to modulate excitability, and cellular activity was measured using voltage sensitive dye Di-4-ANNEPPS. The authors used Mightex’s Polygon400 to control the spatial and temporal activation of CatCh in their cardiac tissue sample. To study anatomical re-entry in their tissue sample, Watanabe et al. used a protocol to artificially induce this process. Watanabe showed that global optogenetic activation of the entire sample disrupted this process. Similarly, patterned illumination of either a 300um or 600um strip in any location on the sample blocked this process. However, changing the depth of the illumination strip (600um wide) affected the likelihood of optogenetic stimulation terminating this process. This paper demonstrates that either local or global optogenetic stimulation can terminate this type of tachycardia.Watanabe, Masaya, Iolanda Feola, Rupamanjari Majumder, Wanchana Jangsangthong, Alexander S. Teplenin, Dirk L. Ypey, Martin J. Schalij, Katja Zeppenfeld, Antoine AF de Vries, and Daniël A. Pijnappels. "Optogenetic Manipulation of Anatomical Re-Entry by Light-Guide Generation of a Reversible Local Conduction Block", Cardiovascular Research, published 23 January 2017.
Inhibitory optogenetic channel GtACR2 can both silence and generate action potentials in cortical neurons
Malyshev, A. Y., Roshchin, M. V., Smirnova, G. R., Dolgikh, D. A., Balaban, P. M., & Ostrovsky, M. A.
A recently published paper in Neuroscience Letters by Malyshev et al. 2017 evaluated the function of inhibitory optogenetic anion channelrhodopsin GtACR2 (chloride channel) using Mightex’s Polygon400 Patterned Illuminator (470nm LED). GtACR2 was expressed in excitatory cortical neurons and the activity of these neurons in slice were recorded using whole-cell electrophysiology. Malyshev et al. 2017 showed that constant illumination with the Polygon400 over the cell body of a GtACR2-expressing cell (695 x 390um) silenced neuronal firing. Conversely, short-light stimulation pulses (up to 10Hz) induced action potentials in GtACR2-expressing neurons. The authors suggest that high chloride concentration in synaptic terminals causes GtACR2 to efflux chloride, which in turn raises the membrane potential leading to action potentials. Further supporting this, using the Polygon400 grid-scanning feature to pseudo-randomly illuminate specific areas (65 x 70um, 10 X 6 grid) in the field of view, Malyshev et al. 2017 showed that illuminating neurons in layer 2/3 or layer 5 induced firing in layer 2/3 GtACR2-expressing cortical neurons, and these areas corresponded to local and long-range connections. This paper demonstrates that this novel optogenetic silencer, depending on the illumination properties, can be used to stimulate or silence neurons and that optogenetic tools should be validated prior to experimentation.
Malyshev, A. Y., Roshchin, M. V., Smirnova, G. R., Dolgikh, D. A., Balaban, P. M., & Ostrovsky, M. A., "Chloride conducting light activated channel GtACR2 can produce both cessation of firing and generation of action potentials in cortical neurons in response to light ", Neuroscience Letters, published 15 February 2017.
Sensory inputs control the integration of neurogliaform interneurons into cortical circuits
Natalia V De Marco Garcia, Rashi Priya, Sebnem N Tuncdemir, Gord Fishell, & Theofanice Karayannis
Figure 1. A DAPI-stained (blue) mouse brain coronal section showing the retrogradely-labeled thalamic cells (red) traced after rabies virus infection of a superficial reelin-positive cortical interneuron.
Neuronal microcircuits in the superficial layers of the mammalian cortex provide the substrate for associative cortical computation. Inhibitory interneurons constitute an essential component of the circuitry and are fundamental to the integration of local and long-range information. Here the authors report that, during early development, superficially positioned Reelin-expressing neurogliaform interneurons in the mouse somatosensory cortex receive afferent innervation from both cortical and thalamic excitatory sources (Figure 1). Using the Mightex Polygon 400 they were able to optimize the activation of channelrhodopsin-expressing terminals from cortical or thalamic afferents and show that they excite distinct postsynaptic NMDA receptors. Abrogation of the NMDA receptors through which the thalamic inputs signal results in defective developmental integration of the cells in the cortical network, through a selective loss of thalamic and a concomitant increase in intracortical connectivity. These results suggest that thalamic inputs are critical in determining the balance between local and long-range connectivity and are fundamental to the proper integration of Reelin-expressing interneurons into nascent cortical circuits. By exploiting the unique capabilities of the Polygon 400 in spatial illumination the authors will next be able to address the effect of activation of subcellular dendritic domains of afferent inputs in developing interneuron input-output transformations.
Natalia V De Marco García, Rashi Priya, Sebnem N Tuncdemir, Gord Fishell & Theofanis Karayannis, "Sensory inputs control the integration of neurogliaform interneurons into cortical circuits", Nature Neuroscience, published online 9 February 2015.
|List of Publications & Articles
Patterned Illumination (More...)
Adrian, Max, et al. "A Phytochrome-Derived Photoswitch for Intracellular Transport." ACS Synthetic Biology (2017).
McBride, Matthew K., et al. "Photoinduced Plasticity in Cross‐Linked Liquid Crystalline Networks." Advanced Materials (2017).
Malyshev, A. Y., et al. "Chloride conducting light activated channel GtACR2 can produce both cessation of firing and generation of action potentials in cortical neurons in response to light." Neuroscience Letters (2017).
Johnson, Heath E., et al."The Spatiotemporal Limits of Developmental Erk Signaling." Developmental Cell (2017).
Watanabe, Masaya, et al. "Optogenetic manipulation of anatomical re-entry by light-guided generation of a reversible local conduction block." Cardiovascular Research (2017).
Duan, Jinggang et al. "Activation of Parvalbumin-Positive Neurons in Both Retina and Primary Visual Cortex Improves the Feature-Selectivity of Primary Visual Cortex Neurons." Neuroscience Bulletin (2017).
Butler, James L., et al. "Intrinsic Cornu Ammonis Area 1 Theta-Nested Gamma Oscillations Induced by Optogenetic Theta Frequency Stimulation." The Journal of Neuroscience (2016).
Fiedler, C. I., et al. "Enhanced mechanical properties of photo-clickable thiol–ene PEG hydrogels through repeated photopolymerization of in-swollen macromer." Soft Matter (2016).
Avants B.W., Murphy D.B., Dapello J.A., Robinson. T.R., NeuroPG: open source software for optical pattern generation and data acquisition. Front. Neuroeng. 8:1.(2015)
García, N. V. D. M., Priya, R., Tuncdemir, S. N., Fishell, G., & Karayannis, T. Sensory inputs control the integration of neurogliaform interneurons into cortical circuits. Nature neuroscience, 18, 393-401 (2015).
LED Sources and LED Controllers (More...)
Kang, J., Chang, J. H., Wilson, B. C., Veilleux, I., Bai, Y., DaCosta, R., ... & Song, T. K. A prototype hand-held tri-modal instrument for in vivo ultrasound, photoacoustic, and fluorescence imaging. Review of Scientific Instruments, 86, 034901 (2015).
Bere, Z., Obrenovitch, T. P., Bari, F., & Farkas, E. Ischemia-induced depolarizations and associated hemodynamic responses in incomplete global forebrain ischemia in rats. Neuroscience, 260, 217-226 (2014).
Wengrowski, A. M., Wang, X., Tapa, S., Posnack, N. G., Mendelowitz, D., & Kay, M. W. Optogenetic release of norepinephrine from cardiac sympathetic neurons alters mechanical and electrical function. Cardiovascular research, cvu258 (2014).
Lee, S., Kruglikov, I., Huang, Z., Fishell, G., & Rudy B., A disinhibitory circuit mediates motor integration in the somatosensory cortex. Nature neuroscience, 16(11), 1662-1670 (2013).]
Cohen, D., Swift, L., Shah, K., Gil, D., Kay, M., Schwartz, A., ... & Mercader, M. Epicardial NADH Fluorescence Images Correlate With Lesion Size and Predict Lesion Depth After Radiofrequency Ablation. Circulation, 128, A11171 (2013).
Stewart, R. S., Huang, C., Arnett, M. T., & Celikel, T. Spontaneous oscillations in intrinsic signals reveal the structure of cerebral vasculature. Journal of neurophysiology, 109(12), 3094-3104 (2013).
Asfour, H., Wengrowski, A. M., Jaimes III, R., Swift, L. M., & Kay, M. W. NADH fluorescence imaging of isolated biventricular working rabbit hearts. Journal of visualized experiments: JoVE, 65 (2012).
Wang, M., Chazot, P. L., Ali, S., Duckett, S. F., & Obrenovitch, T. P. Effects of NMDA receptor antagonists with different subtype selectivities on retinal spreading depression. British journal of pharmacology, 165(1), 235-244 (2012).
Swift, L. M., Asfour, H., Posnack, N. G., Arutunyan, A., Kay, M. W., & Sarvazyan, N. Properties of blebbistatin for cardiac optical mapping and other imaging applications. Pflügers Archiv-European Journal of Physiology, 464(5), 503-512 (2012).
Xia, Y., Driscoll, J. R., Wilbrecht, L., Margolis, E. B., Fields, H. L., & Hjelmstad, G. O. Nucleus accumbens medium spiny neurons target non-dopaminergic neurons in the ventral tegmental area. The Journal of Neuroscience, 31(21), 7811-7816 (2011).
Farkas, E., Bari, F., & Obrenovitch, T. P. Multi-modal imaging of anoxic depolarization and hemodynamic changes induced by cardiac arrest in the rat cerebral cortex. Neuroimage, 51(2), 734-742 (2010).
Farkas, E., Pratt, R., Sengpiel, F., & Obrenovitch, T. P. Direct, live imaging of cortical spreading depression and anoxic depolarisation using a fluorescent, voltage-sensitive dye. Journal of Cerebral Blood Flow & Metabolism, 28, 251-262 (2008).