Ian Parker

Picture of Ian Parker
Distinguished Professor, Neurobiology and Behavior
School of Biological Sciences
Distinguished Professor, Physiology & Biophysics
School of Medicine
Ph.D., University College, London, 1984
Phone: (949) 824-7332
Fax: (949) 824-2447
Email: iparker@uci.edu
University of California, Irvine
1217 McGaugh Hall
Mail Code: 4550
Irvine, CA 92697
Research Interests
Calcium signaling; second messengers; inositol trisphosphate; confocal microscopy; two-photon microscopy; total internal reflection microscopy; superresolution imaging; lasers
Research Abstract
Our interests lie in the area of cell signaling, i.e. the ways in which cells communicate with each other as well as within themselves.

To study these processes we have developed optical techniques for stimulating intracellular messenger pathways and for recording the resulting changes in intracellular free calcium. Photolabile "caged" compounds, such as caged inositol trisphosphate can be loaded into cells and then be induced to release a precisely controlled amount of free messenger by stimulation with a flash of ultraviolet light. For example, calcium that is liberated from intracellular stores by the photo released inositol trisphosphate can then be recorded using laser confocal and two-photon imaging of fluorescence signals from long wavelength calcium indicator dyes.

Projects presently underway in the lab include:

1. Investigation of the mechanisms underlying the generation of 'elementary' calcium signals, and their roles in generating global cellular calcium signals.

2. Multi-scale modeling of cellular calcium signaling, from single channels to whole cell (Collaborations with Dr. John Pearson, Los Alamos; Dr. Jian-Wei Shuai, Xiaming China; Dr. Kevin Foskett, U. Penn.; and Dr. Silvina Ponce-Dawson, Buenos Aires).

3. Studies of IP3-mediated calcium signaling in cortical and cerebellar neurons, and its involvement in pathogenesis of Alzheimer's disease. (Collaboration with Dr. Frank LaFerla, UCI)

4. Functional imaging of lymphocyte motility and calcium signaling by two-photon microscopy within intact lymph nodes. (Collaboration with Dr. Mike Cahalan, UCI).

5. Construction of total internal reflection microscope systems to calcium channel function and localization in the plasma and ER membranes at the single-molecule level.

6. Studies of cellular calcium signaling disruptions in familial hemiplegic migraine (collaboration with Dr. Jay Gargus, Physiology & Biopphysics, UCI).

7. Single-molecule studies of calcium influx pathway proteins STIM and ORAI (Collaboration with Dr. Mike Cahalan, Physiology & Biophysics, UCI).

For more information, please click on the link above to go to our LAB WEBSITE (http://parkerlab.bio.uci.edu/index.htm). This contains a full list of publications, including downloadable pdf files; as well as pictures, movies; complete instructions on building your own two-photon microscope; and lots more good stuff.
Available Technologies
Awards and Honors
Excellence in Teaching Award, School of Biological Sciences, UCI. 2001
Fellow of the Royal Society (U.K.). 2008
Fellow of the American Association for the Advancement of Science. 2009
Norman Weinberger Award for Lifetime Achievement in Research: Department of Neurobiology & Behavior, UC Irvine. 2012
NIH MERIT Award. 2011-2022
Pensalfini A, Umar AR, Glabe C, Parker I, Ullah G, Demuro A. Intracellular Injection of Brain Extracts from Alzheimer's Disease Patients Triggers Unregulated Ca2+ Release from Intracellular Stores That Hinders Cellular Bioenergetics. Cells. 2022 Nov 16;11(22):3630. doi: 10.3390/cells11223630. PMID: 36429057; PMCID: PMC9688564.
Vorontsova I, Lock JT, Parker I. KRAP is required for diffuse and punctate IP3-mediated Ca2+ liberation and determines the number of functional IP3R channels within clusters. Cell Calcium. 2022 Nov;107:102638. doi: 10.1016/j.ceca.2022.102638. Epub 2022 Aug 19. PMID: 36030740; PMCID: PMC9588678.
Jairaman A, McQuade A, Granzotto A, Kang YJ, Chadarevian JP, Gandhi S, Parker I, Smith I, Cho H, Sensi SL, Othy S, Blurton-Jones M, Cahalan MD. TREM2 regulates purinergic receptor-mediated calcium signaling and motility in human iPSC-derived microglia. Elife. 2022 Feb 22;11:e73021. doi: 10.7554/eLife.73021. PMID: 35191835; PMCID: PMC8906810.
Jeffrey T.Lock and Ian Parker. Termination of Ca2+ puffs during IP3-evoked global Ca2+ signals. 2021 Cell Calcium; https://doi.org/10.1016/j.ceca.2021.102494
Jairaman, A., Othy, S., Dynes, J. L., Yeromin, A. V., Zavala, A., Greenberg, M. L., Nourse, J. L., Holt, J. R., Cahalan, S. M., Marangoni, F., Parker, I., Pathak, M. M., & Cahalan, M. D. (2021). Piezo1 channels restrain regulatory T cells but are dispensable for effector CD4+ T cell responses. Science advances, 7(28), eabg5859. https://doi.org/10.1126/sciadv.abg5859
Othy S, Jairaman A, Dynes JL, et al. Regulatory T cells suppress Th17 cell Ca2+ signaling in the spinal cord during murine autoimmune neuroinflammation. Proc Natl Acad Sci U S A. 2020;117(33):20088-20099. doi:10.1073/pnas.2006895117
Vais H, Wang M, Mallilankaraman K, et al. ER-luminal [Ca2+] regulation of InsP3 receptor gating mediated by an ER-luminal peripheral Ca2+-binding protein. Elife. 2020;9:e53531. Published 2020 May 18. doi:10.7554/eLife.53531
Lock JT, Parker I. IP3 mediated global Ca2+ signals arise through two temporally and spatially distinct modes of Ca2+ release. Elife. 2020;9:e55008. Published 2020 May 12. doi:10.7554/eLife.55008
Swaminathan D, Dickinson GD, Demuro A, Parker I. Noise analysis of cytosolic calcium image data. Cell Calcium. 2020;86:102152. doi:10.1016/j.ceca.2019.102152
Ellefsen KL, Holt JR, Chang AC, et al. Myosin-II mediated traction forces evoke localized Piezo1-dependent Ca2+ flickers. Commun Biol. 2019;2:298. Published 2019 Aug 7. doi:10.1038/s42003-019-0514-3
Lock JT, Smith IF, Parker I. Spatial-temporal patterning of Ca2+ signals by the subcellular distribution of IP3 and IP3 receptors. Semin Cell Dev Biol. 2019;94:3-10. doi:10.1016/j.semcdb.2019.01.012
Lock, J.T., Alzayady, K.J., Yule, D.I. & Parker, I. All three IP3 receptor isoforms generate Ca2+ puffs that display similar characteristice. Sci. Signal 11, eaau0344. doi:10.1126/scisignal.aau0334. 2018.
Kyle L. Ellefsen, Jeffrey T. Lock, Brett Settle, Carley A. Karsten & Ian Parker. Applications of FLIKA, a Python-based image processing and analysis platform, for studying local events of cellular calcium signaling. BBA Molecular Cell Research. 2018. doi.org/10.1016/j.bbamcr.2018.11.012.
Shah SI, Smith M, Swaminathan D, Parker I, Ullah G, Demuro A. Cell Speks: A software for Automated Detection and Analysis of Calcium Channels in live cells. Biophys J. 2018 Oct 25. pii: S0006-3495(18)31163-9. doi: 10.1016/j.bpj.2018.10.015.
Shah, S., Demuro, A., Mak, D-O. D., Parker, I., Pearson, J.E. & Ullah, G. TraceSpecs: A software for automated idealization of noisy patch-clamp and imaging data. Biophys. J. 115;9-21. doi.org/10.1016/j.bpi.2018.06.003. PDF
Ma Z, Taruno A, Ohmoto M, Jyotaki M, Lim JC, Miyazaki H, Niisato N, Marunaka Y, Lee RJ, Hoff H, Payne R, Demuro A, Parker I, Mitchell CH, Henao-Mejia J, Tanis JE, Matsumoto I, Tordoff MG, Foskett JK. CALHM3 Is Essential for Rapid Ion Channel-Mediated Purinergic Neurotransmission of GPCR-Mediated Tastes. Neuron. 98:547-561 doi: 10.1016/j.neuron.2018.03.043. 2018
Ellefsen, K.L. & Parker, I. Dynamic Ca2+ imaging with a simplified lattice light-sheet microscope: A sideways view of subcellular Ca2+ puffs. Cell Calcium 71:34-44. doi:10.1016/j/ceca.2017.11.005. 2018
Tobias X Dong, Shivashankar Oth, Milton L Greenberg, Amit Jairaman, Chijioke Akunwafo, Sabrina Leverrier, Ying Yu, Ian Parker, Joseph L Dynes, Michael D Cahalan. Intermittent Ca2+ signals mediated by Orai1 regulate basal T cell motility. Elife ;6:e27827 doi: 10.7554/eLife.27827. 2017
Tobias X Dong, Shivashankar Othy, Amit Jairaman, Jonathan Skupsky, Angel Zavala, Ian Parker, Joseph L Dynes, Michael D Cahalan. T cell calcium dynamics visualized in a ratiometric tdTomato-GCaMP6F transgenic reporter mouse. Elife 2017;6:e32417 doi: 10.7554/eLife.32417
Parker, I., Evans, K.T., Ellefsen, K., Lawson, D.A. & Smith, I. Lattice light sheet imaging of membrane nanotubes between human breast cancer cells in culture and in brain metastases. Nature Scientific Reports 7: 11029 DOI:10.1038/s41598-017-11223-y. 2017.
Schmunk, G., Nguyen, R.L., Ferguson, D.L., Kumar, K., Parker, I. & Gargus, J.J.
High-throughput screen detects calcium signaling dysfunction in typical sporadic autism spectrum disorder. Sci. Rep. Feb 1;7:40740. DOI 1038/srep40740. 2017.
Lock, J.T., Smith, I.F. & Parker , I. Comparison of Ca2+ puffs evoked by extracellular agonists and photoreleased IP3. Cell Calcium e-pub ahead of print. DOI 10.1016/j.ceca2016.11.006. 2016
Dickinson, G.D., Ellefsen, K.L., Ponce-Dawson, S., Pearson, J.E. & Parker, I. Hindered cytoplasmic diffusion of inositol trisphosphate hinders its cellular range of action. Science Signaling. Vol 9, issue 453, pp. ra108. DOI: 10.1126/scisignal.aag1625. 2016. Commentary by Luc Laybaert. IP3 still on the move but now in the slow lane. Sci. Signal. Vol 9, Issue 453, pp. fs17. DOI: 10.1126/scisignal.aaI1929. 2016.
Lock, J.T., Parker, I. & Smith, I. Communication of Ca2+ signals via tunneling membrane nanotubes is mediated by transmission of inositol trisphosphate through gap junctions. Cell Calcium doi:10.1016/ju.ceca.2016.06.004. 2016.
Schmunk, G., Boubion, B.J., Smith, I.F., Parker, I. & Gargus, J.J. Shared functional defect in IP3R-mediated calcium signaling in diverse monogenic autism syndromes. Nature Trans. Psychiatry 5:e643; doi:10.1038/tp.2015.123. 2015.
Jason Weinger, Milton L Greenberg, Melanie P Matheu, Ian Parker, Craig M Walsh, Thomas E Lane, Michael D Cahalan. Two-Photon Imaging of Cellular Dynamics in the Mouse Spinal Cord. Journal of Visualized Experiments. doi: 10.3791/52580. 2015. http://www.jove.com/video/52580/t
Lock, J.T., Ellefsen, K.L., Settle, B., Parker, I. & Smith, I.F. Imaging local Ca2+ signals in cultured mammalian cells. Journal of Visualized Experiments. 3;(97). doi: 10.3791/52516. 2015.
Potkin, S., Tan, Z., Dai, W., van Erp, T., Overman, J., Demuro, A., Digman, M., Hatami, A., Albay, R., Sontag, E., Potkin, K., Ling, S., Macciardi, F., Bunney, W., Long, J., Paulsen, J., Ringman, J., Parker, I., Glabe, C., Thompson, L., and Chiu, W. Huntington's disease cerebrospinal fluid seeds aggregation of mutant Huntingtin. Mol. Psych. doi: 10.1038/mp.2015.81. [Epub ahead of print] 2015.
Matheu, M.P., Shivashankar, O., Greenberg, M.L., Dong, T.X., Schujis, M., Deswarte, K., Hammad, H., Lambrecht, B.N., Parker, I. & Cahalan, M. Imaging endogenous regulatory T cell dynamics and suppression of helper T cell priming mediated by CTLA-B7 interactions. Nat. Commun. doi: 10.1038/ncomms7219. 2015.
Amcheslavsky, A., Wood, M., Yeromin, A.V., Parker, I., Freites, J.A., Tobias, D.J. & Cahalan, M. Molecular Biophysics of Orai store-operated channels. Biophys. J. 108:237-246. 2015.
M. Ruckl, I. Parker, J.S. Marchant, Ch. Nagaiah, F.W. Johenning & S. Rudiger. Modulation of elementary calcium release mediates a transition from puffs to waves in an IP3R cluster model. PLoS Computational Biol. DOI: 10.1371/journal.pcbi.1003965 (2015).
Sanderson, M.J., Smith, I., Parker, I. & Bootman, M. Fluorescence microscopy. Cold Spring Harb. Protoc. doi: 10.1101/pdb.top071795 2014.
Ellefsen, K., Settle, B., Parker, I. & Smith, I. An algorithm for automated detection, localization and measurement of local calcium signals from camera-based imaging. Cell Calcium 56:147-156, 2014.
Wiltgen, S.M., Dickinson, G.D., Swaminathan, D. & Parker, I. Termination of calcium puffs and coupled closings of inositol trisphosphate receptor channels. Cell Calcium 56:157-168, 2014.
Ian F. Smith, Divya Swaminathan, George D. Dickinson and Ian Parker. Single-molecule tracking of inositol trisphosphate receptors reveals differing motilities and distributions . Biophys. J. 107:834-845, 2014.
Milton L. Greenberg, Jason G. Weinger, Melanie P. Matheu, Kevin S. Carbajal, Ian Parker, Wendy B. Macklin, Thomas E. Lane, and Michael D. Cahalan. Two-photon imaging demonstrates remyelination of spinal cord axons by engrafted neural precursor cells in a viral model of multiple sclerosis. PNAS 111:E2349-2355, 2014.
Dickinson, G.D. & Parker, I. Factors determining the recruitment of inositol trisphosphate receptor channels during calcium puffs. Biophys. J. 105:2474-2484, 2013.
Greenberg, M.L., Yu, Y., Leverrier, S., Zhang, S.L., Parker, I. & Cahalan, M.D. Orai1 Function is Essential for T Cell Homing to Lymph Nodes. J. Immunol. doi:10.4049/jimmunol.1202212, 2013.
Matheu, M.P., Teijaro, J.R., Walsh, K.B., Greenberg, M.L., Marsolais, D., Rosen, H., Oldstone, M.B.A. & Cahalan, M.D. Three phases of CD8 T cell response in the lung following H1N1 influenza infection and sphingosine 1 phosphate agonist therapy. PLoS One 8(3):e58033. doi: 10.1371/journal.pone.0058033. 2013.
Demuro, A. & Parker, I. Cytotoxicity of intracellular A?42 amyloid oligomers involves Ca2+ release from the ER by stimulated production of inositol trisphosphate. J. Neurosci. 33:3824-3833, 2013.
Adam P. Siebert, Zhongming Ma, Jeremy D. Grevet, Angelo Demuro, Ian Parker, and J. Kevin Foskett. Structural and Functional Similarities of Calcium Homeostasis Modulator 1 (CALHM1) Ion Channel With Connexins, Pannexins and Innexins. J. Biol. Chem.288:6140-6153, 2013
Dickinson, G.D. & Parker, I. Temperature-dependence of IP3-mediated local and global Ca2+ signals. Biophys. J. 104:386-396, 2013.
Yamasaki-Mann, M., Demuro, A. & Parker, I. Cytosolic [Ca2+] regulation of IP3-evoked puffs. Biochem. J., 449:167-173, 2013.
Ullah, G., Parker, I., Mak, D-O. & Pearson, J.E. Multi-scale data-driven modeling and observation of calcium puffs. Cell Calcium 52:152-160, 2012.
Matheu, M.P., Su, Y., Greenberg, M.L., Blanc, C.A., Parker, I., Scott, D.W. & Cahalan, M. D. Toll-like receptor 4-activated B cells out-compete Toll-like receptor 9-activated B cells to establish peripheral immunological tolerance. PNAS 109:E1258-1266, 2012.
Dickinson, G.D., Swaminathan, D. & Parker, I. The probability of triggering calcium puffs is linearly related to the number of inositol trisphosphate receptors in a cluster. Biophys. J. 102:1826-1836, 2012
Thurley, K., Smith, I., Tovey, S.G., Taylor, C.W., Parker, I. & Falcke, M. Time scales of IP3-evoked Ca2+ spikes emerge from Ca2+ puffs only at the cellular level. Biophys. J. 101:2638-2644, 2011.
Demuro, A., Smith, M. & Parker, I. Single-channel Ca2+ imaging implicates A? 1-42 amyloid pores in Alzheimer's disease pathology. J. Cell Biol. 195:515-524, 2011.
Demuro, A., Penna, A., Safrina, O., Yeromin, A.V., Amcheslasvsk, A., Cahalan, M.D. & Parker, I. Subunit stoichiometry of human Orai1 and Orai3 in closed and open states. Proc. Natl. Acad. Sci. USA.(2011: online publication ahead of print. www.pnas.org/cgi/doi/10.1073/pnas.1114814108
Yamasaki-Mann, M., & Parker, I. Enhanced ER Ca2+ store filling by overexpression of SERCA2B promotes IP 3-evoked puffs. Cell Calcium 50:36-41 (2011).
Smith, I.F., Shuai, J., & Parker, I. Active generation and propagation of Ca2+ signals within tunneling membrane nanotubes. Biophys. J. 100:pL37-39, 2011.
Parker, I. & Smith, I.F. Recording single channel activity of inositol trisphosphate receptors in intact cells with a microscope, not a patch clamp. J. Gen. Physiol. 136:119-127, 2010.
Yamasaki-Mann, M., Demuro, A. & Parker, I. Modulation of ER Ca2+ store filling by cADPR promotes IP3-evoked Ca2+ signals. J. Biol. Chem. (e-pub ahead of print) PMID 20538594, 2010.
Wiltgen, S., Smith, I. & Parker, I. Super-resolution localization of single functional IP3R channels utilizing Ca2+ flux as a readout. Biophys. J. 99:437-446, 2010.
Cárdenas, C., Miller, R.A., Smith, I, Bui, T., Molgó, J., Muller, M., Horia Vais, H., Cheung, K-H., Yang, J., Parker, I., Thompson, C., Birnbaum, M., Hallows, K.R. & Foskett, J.K. Essential Regulation of Cell Bioenergetics by Constitutive Inositol Trisphosphate Receptor Ca2+ Release. Cell 142:270-283, 2010. Commentary by Green & Wang, 'Calcium and Energy: Making the cake and eating it too?'. Cell 142:200-202, 2010.
Reissner, K.J., Pu, L., Schaffhausen, J.H., Boyle, H.B., Smith, I.F., Parker, I. & Carew, T.J. A Novel Postsynaptic Mechanism for Heterosynaptic Sharing of Short-Term Plasticity. J. Neurosci. 30:8797-8806, 2010.
Sen, D., Forrest, L., Kepler, T.B., Parker, I. & Cahalan, M.D. Selective and site-specific mobilization of dermal dendritic cells and Langerhans cells by Th1- and Th2-polarizing adjuvants. Proc. Natl. Acad. Sci. USA.107:8334-8339, 2010.
Garrod, K.R., Liu, F-C., Forrest, L.E., Parker, I., Kang, S-M. & Cahalan, M.D. NK cell patrolling and elimination of allogeneic dendritic cells favors indirect allo-presentation by syngeneic dendritic cells. J. Immunol. 184:2392-2336, 2010.
Smith, I.F., Wiltgen, S.W., Shuai, J & Parker, I. Ca2+ puffs originate from preestablished clusters of inositol trisphosphate receptors. Science Signaling 2: Issue 98 ra77, 2009.
Parker, I. & Cahalan, M.D. Immunology based on nonlinear optical microscopy. In: Handbook of Nonlinear Optical Microscopy. Eds. So, P. & Masters, B. Oxford University Press. 2008
Zeller S, Rüdiger S, Engel H, Sneyd J, Warnecke G, Parker I, Falcke M. Modeling of the modulation by buffers of Ca2+ release through clusters of IP3 receptors. Biophys. J. 97:992-1002, 2009.
Zinselmeyer BH, Dempster J, Wokosin DL, Cannon JJ, Pless R, Parker I, Miller MJ. Two-photon microscopy and multidimensional analysis of cell dynamics. Meth. Enzymol. 461:349-378, 2009.
Smith, I. & Parker, I. Imaging the quantal substructure of single IP3R channel activity during Ca2+ puffs in intact mammalian cells. Proc. Natl. Acad. Sci. USA 106:6404-6409, 2009.
Yamasaki, M., Demuro, A. & Parker, I. cADPR modulates SERCA activity in Xenopus oocytes. Cell Calcium 45:293-9, 2009.
Smith, I.F., Wiltgen, S.M. & Parker, I. Localization of puff sites adjacent to the plasma membrane : Functional and spatial characterization of Ca2+ signaling in SH-SY5Y cells using membrane-permeant caged IP3. Cell Calcium 45:65-76, 2009.
Sen, D., Deerinck, T.J. Ellisman, M.H., Parker, I., Cahalan, M.D. Quantum dots for tracking dendritic cells and priming an immune response in vitro and in vivo. PLoS ONE 3:e3290, 2008
Cahalan, M.D. & Parker, I. Choreography of cell motility and interaction dynamics imaged by two-photon microscopy in lymphoid organs. Ann. Rev. Immunol. 26:585-626, 2008 .
Matheu, M.P., Beeton, C., Garcia, A., Chi, V., Rangaraju, S., Safrina, O., Monaghan, K., Uemura, M.I., Li, D., Pal, S., de la Maza, L.M., Monuki, E., Flugel, A., Pennington, M.W., Parker, I., Chandy, K.G. & Cahalan, M.D. Imaging of effector memory T cells during a delayed-type hypersensitivity reaction and suppression by KV1.3 channel block. Immunity 29:602-614, 2008.
Shuai, J., Pearson, J. & Parker, I. Modeling Ca2+ feedback on a single inositol 1,4,5-trisphosphate receptor and its modulation by Ca2+ buffers. Biophysical Journal. 95:3738-3752, 2008.
Green, K.N., Demuro, A., Akbari, Y., Hit, B.D., Smith, I.F., Parker, I. & LaFerla, F.M. SERCA pump activity is physiologically regulated by presenilin and regulates amyloid ? production. J. Cell. Biol. 181:1107-1116, 2008.
Demuro, A. & Parker, I. Multi-dimensional resolution of elementary Ca2+ signals by simultaneous multi-focal imaging. Cell Calcium 43:367-374, 2008
Oak, J.S, Matheu, M.P., Parker, I. Cahalan, M.D. & Fruman, D.A. Lymphocyte motility: The twisting, turning tale of phosphoinositide 3-kinase. Biochem. Soc. Trans. 35:1109-1113, 2007.
Stutzmann, G.E, Smith, I., Caccamo, A., Oddo, S., Parker, I. & LaFerla, F. Enhanced ryanodine-mediated calcium release in mutant PS1-expressing Alzheimer's mouse models. Ann. N.Y. Acad. Sci. 1097:265-277 (2007).
Ionescu, L., White, C., Cheung, K-H., Shuai, J., Parker, I., Pearson, J.E., Foskett, J.K. & Mak, D-O.D. Modal switching is the major mechanism of ligand regulation of InsP3 receptor calcium release channels. J. Gen. Physiol. DOI:10.1085/jgp.200709859, 2007.
Garrod KR, Wei SH, Parker I, & Cahalan MD. Natural killer cells actively patrol peripheral lymph nodes forming stable conjugates to eliminate MHC-mismatched targets. Proc. Natl. Acad. Sci. USA. 104:12081-12086, 2007.
Wei, S.H., Safrina, O., Yu, Y., Garrod, K.R., Cahalan, M.D & Parker, I. Ca2+ signals in CD4+ T cells during early contacts with antigen-bearing dendritic cells in lymph node. J. Immunol. 179:1586-1594, 2007.
Matheu, M.P., Deane, J.A., Parker, I., Fruman, D.A. & Cahalan, M.D. Class IA Phosphoinositide 3-Kinase modulates basal lymphocyte motility in the lymph node. J. Immunol. 179:2261-2269, 2007.
Shuai, J.W., Pearson, J.E., Foskett, J.K., Mak, D.-O. & Parker, I. A Kinetic Model of Single and Clustered IP3 Receptors in the Absence of Ca2+ Feedback. Biophys. J. 93:1151-1162, 2007.
Rudiger, S., Shuai, J.W., Huisinga, W., Chamakuri, N., Warnecke, G., Parker, I. & Falcke, M. Hybrid stochastic and deterministic simulations of calcium blips. Biophys. J. 93:1847-57, 2007.
Shuai, J., Rose, H.J. & Parker, I. The Number and Spatial Distribution of IP3 Receptors Underlying Calcium Puffs in Xenopus Oocytes. Biophys. J. 91:4033-4044, 2006.
Rose, H.J., Dargan, S., Shuai, J. & Parker, I. ‘Trigger’ Events Precede Calcium Puffs in Xenopus Oocytes. Biophys. J. 91:4024-4032, 2006.
Demuro, A., Parker, I. Imaging single-channel calcium microdomains. Cell Calcium 40:413-422, 2006.
Cahalan, M.D. & Parker, I. Imaging the Choreography of Lymphocyte Trafficking and the Immune Response. Curr. Op. Immunol. 18:1-7, 2006.
Stutzmann, G.E., Smith, I., Caccamo, A., Odo, S., LaFerla, F. & Parker, I. Enhanced ryanodine receptor recruitment contributes to Ca2+ disruptions in young, adult and aged Alzheimer’s disease mice. J. Neurosci. 26:5180-5189, 2006.
Parker, I. Plasmalemmal calcium signaling in arterial smooth muscle: It’s elementary! J. Gen. Physiol. 127:650-609, 2006.
Sanna, M.G., Wang, S-K., Gonzalez-Cabrera, P.J., Don, A.m Marsolais, D., Matheu, M.P., Wei, S.H., Parker, I., Jo, E., Cheng, W-C., Cahalan, M.D. & Rosen, H. Enhancement of capillary leakage and restoration of lymphocyte egress by a chiral S1P1 antagonist in vivo. Nature Chemical Biology. 2:434-441, 2006.
Fraiman, D.E., Pando, B., Dargan, S., Parker, I. & Ponce-Dawson, S. Analysis of puff dynamics in oocytes: interdependence of puff amplitude and inter-puff interval. Biophys. J. 90:3897-3907, 2006.
Wei, S.H., Rosen, H., Matheu, M.P., Sanna, M.G., Wong, C.-H., Parker, I. & Cahalan, M.D. Reversible inhibition of T cell lymph node egress by S1P1 receptor agonism shown by two-photon imaging. Nature Immunol. 6:1228-1235, 2005.
Demuro, A., Parker, I. & Glabe, C.G. Calcium dysregulation and membrane disruption as a ubiquitous neurotoxic mechanism of soluble amyloid oligomers. J. Biol. Chem. 280: 17294-17300, 2005.
Thorn, P. & Parker, I. Two phases of zymogen granule lifetime in mouse pancreas: ghost granules linger after exocytosis of contents. J. Physiol. 563: 433-442, 2005.
Stutzmann, G.E. & Parker, I. Dynamic multi-photon imaging: from cells to systems. Physiology 20:15-21, 2005.
Cahalan MD and Parker I. Close encounters of the first and second kind: T-DC and T-B interactions in the lymph node. Seminars in Immunology 17:442-451, 2005
Wei, S.H., Rosen, H., Matheu, M.P., Sanna, M.G., Wang, S.-K., Wong, C.-H., Parker, I. & Cahalan, M.D. Sphingosine 1-phosphate type 1 receptor agonism inhibits transendothelial migration of medullary T cells to lymphatic sinuses. Nature Immunology 6:1228-1235, 2005
Demuro, A. & Parker, I. ‘Optical patch-clamping’: single-channel recording by imaging Ca2+ flux through individual muscle acetylcholine receptor channels. J. Gen. Physiol. 126:179-192, 2005.
Zinselmeyer, B.H., Dempster, J., Gurney, A.M., Wokosin, D., Miller, M., Ho, H., Parker, I. Cahalan, M.D., Brewer, J.M. & Garside, P. In situ characterization of antigen-specific CD4+ T cells in mucosal and systemic lymphoid tissues during the induction of oral priming and oral tolerance. . J. Exp. Med. 201:1815-1823, 2005.
Okada, T., Miller, M.J., Parker, I., Krummel, M.F., Neighbors, M., Hartley, S.., O’Garra, A., Cahalan, M.D. & Cyster, J.G. Antigen-engaged B cells undergo directional migration to the T zone and form motile conjugates with helper T cells. PLoS Biol. 3(6):e150, 2005.
Demuro, A. & Parker, I. Imaging single-channel calcium microdomains by total internal reflection microscopy. Bio. Res. 37(4):675-9, 2004.
Demuro, A., Mina, E., Kayed, R., Milton, S.C., Parker, I. , & Glabe, C.G. Calcium dysregulation and membrane disruption as a ubiquitous neurotic mechanism of soluble amyloid oligomers. J. Biol. Chem. 280: 17294-17300, 2005.
Thorn, P. & Parker, I. Two phases of zymogen granule lifetime in mouse pancreas: ghost granules linger after exocytosis of contents. J. Physiol. 563;433-442 (2005)
Shuai, J. & Parker, I. Optical single-channel recording by imaging Ca2+ flux through individual ion channels: theoretical considerations and limits to resolution. Cell Calcium 37: 283-299, 2005.
Ventura, A.C., Bruno, L., Demuro, A., Parker, I. & Ponce-Dawson, S. A model-independent algorithm to derive Ca2+ fluxes underlying local cytosolic Ca2+ transients. Biophys. J. 88: 2403-2421, 2005
Stutzmann, G.E. & Parker, I. Dynamic multi-photon imaging: a live view from cells to systems. Physiology 20:15-21, 2005.
Demuro, A. and Parker, I. Imaging the activity of single calcium channels: ‘optical patch-clamp recording’ Physiology News 55:24-26 (2005).
Miller, M.J., Safrina, O., Parker, I. & Cahalan, M.D. Imaging the single-cell dynamics of CD4+ T cell activation by dendritic cells in lymph nodes. J. Exp. Med. 200: 847-856, 2004.
Demuro, A. & Parker, I. Optical single-channel recording: Imaging Ca2+ flux through individual ion channels with high temporal and spatial resolution. J. Biomed. Opt. 10: 011002-1-8, 2005.
Dargan, S., Schwaller, B. & Parker, I. Spatiotemporal patterning of IP3-mediated Ca2+ signals in Xenopus oocytes by Ca2+-binding proteins. J. Physiol. 556: 447-461, 2004.
Thorn, P., Fogarty, K.E. & Parker , I. Zymogen granule exocytosis is characterized by long fusion pore openings and preservation of vesicle lipid identity. Proc. Natl. Acad. Sci. 101: 6774-6779, 2004
Syed, I.S., Demuro, A., Mak, D-O. D., Parker, I., Pearson, J.E. & Ullah, G. TraceSpecks: a software for automated idealization of noisy patch-clamp and imaging data. Biophys. J. 115:9-21. doi: 10.2337/dc18-0288. 2018
Milton L. Greenberg, Jason G. Weinger, Melanie P. Matheu, Kevin S. Carbajal, Ian Parker, Wendy B. Macklin, Thomas E. Lane, and Michael D. Cahalan. Two-photon imaging demonstrates remyelination of spinal cord axons by engrafted neural precursor cells in a viral model of multiple sclerosis. PNAS 111:E2349-2355, 2014.
Shah SI, Smith M, Swaminathan D, Parker I, Ullah G, Demuro A. Cell Speks: A software for Automated Detection and Analysis of Calcium Channels in live cells. Biophys J. 2018 115:2141-2151. doi: 10.1016/j.bpj.2018.10.015. [Epub ahead of print] PDF
Jeffrey T. Lock, Ian Parker. Termination of Ca2+ puffs during IP3-evoked global Ca2+ signals. 2021. Cell Calcium; https://doi.org/10.1016/j.ceca.2021.102494
Jeffrey T. Lock & Ian Parker. Termination of Ca2+ puffs during IP3-evoked global Ca2+ signals. 2021. Cell Calcium
Lock, J., Smith I.F. & Parker, I. Spatio-temporal patterning of Ca2+ signals by the subcellular distribution of IP3 and IP3 receptors. Semin Cell Dev Biol. 2019;94:3-10. doi:10.1016/j.semcdb.2019.01.012
Demuro, A. & Parker, I. Imaging the activity and localization of single voltage-gated Ca2+ channels by total internal reflection fluorescence microscopy. Biophys. J. 86:3250-3259, 2004.
Stutzmann, G.E., Caccamo, A., LaFerla, F.M. & Parker, I. Dysregulated IP3 signaling in cortical neurons of knock-in mice expressing an Alzheimer’s-linked mutation in presenilin 1 results in exaggerated Ca2+ signals and altered membrane excitability. J. Neurosci. 24:508-513, 2004.
Miller, M.J., Hejazi, A.S., Wei, S.H., Cahalan, M.D. & Parker, I. T cell repertoire scanning is promoted by dynamic dendritic cell behavior and random T cell motility in the lymph node. Proc. Natl. Acad. Sci. 101, 998-1003, 2004.
Miller, M.J., Wei, S.H., Parker, I. & Cahalan, M.D. A stochastic view of lymphocyte motility and trafficking within the lymph node. Immunol. Rev. 195: 136-159, 2003
Dargan, S.L and Parker, I. Buffer kinetics shape the spatiotemporal patterns of IP3-mediated Ca2+ signals. J. Physiol. 553:775-788, 2003
Demuro, A. & Parker, I. Optical single-channel recording: Imaging Ca2+ flux through individual N-type voltage-gated channels. Cell Calcium 34:499-509, 2003.
Autonomous T cell trafficking examined in vivo using intravital 2-photon microscopy., Miller, M.J., Wei, S.H., Cahalan, M.D. & Parker, I., Miller, M.J., Wei, S.H., Cahalan, M.D. & Parker, I. Autonomous t cell trafficking examined in vivo with intravital two-photon microscopy. Proc. Natl. Acad. Sci. USA 100:2604-2609, 2003
Subramanian, V.S., Marchant, J.S., Parker, I. & Said, H. Cell biology of the human thiamine transporter-1 (hTHTR1): intracellular trafficking and membrane targeting mechanisms. J. Biol. Chem. 278: 3976-3984, 2003.
Stutzmann, G.E., LaFerla, F.M. & Parker, I. Ca2+ signaling in mouse cortical neurons studied by 2-photon imaging and photoreleased IP3. J. Neurosci. 23: 758-765, 2003.
Marriott, G. & Parker, I. (Eds.) Biophotonics, parts A & B. Methods in Enzymology vols. 360, 361, 2003
Cahalan, M.D., Miller, M.J., Wei, S.H. & Parker, I. Real-time imaging of lymphocytes in vivo. Curr. Op. Imunol 15:372-377, 2003.
Miller, M.J., Wei, S.H., Cahalan, M.D. & Parker, I. Two photon tissue imaging: Seeing the immune system in a fresh light. Nat. Rev. Immunol. 2:872-880, 2002
Marchant, J.S., Subramanian, V.S., Parker, I. & Said, H.M. Intracellular trafficking and membrane targeting mechanisms of the human reduced folate carrier in mammalian epithelial cells. J. Biol. Chem. 277: 33325-3333, 2002.
Miller, M.J., Wei, S.H., Parker, I. & Cahalan, M.D. Two-photon imaging of living T and B lymphocytes in mouse lymph node. Science, 296: 1869-1873, 2002. (published online 16 May 2002 : 10.1126/science.1070051)
Marchant, J.S., Ramos, V. & Parker, I. Structural and functional relationship between mitochondria and elementary Ca2+ release sites in Xenopus oocytes. Am. J. Physiol. 282:C1374-1386, 2002.
Nguyen, Q.-T., Callamaras, N., Hsieh, C. & Parker, I. Construction of a two-photon microscope for video-rate Ca2+ imaging. Cell Calcium 30:383-393, 2001.
Marchant, J.S., Stutzmann, G.E., Leissring, M.A., LaFerla, F. & Parker, I. Multiphoton-evoked color change of DsRed as an optical highlighter for cellular and sub-cellular labeling. Nature Biotechnology 19:645-649, 2001.
Marchant, J.S. & Parker, I. Role of elementary Ca2+ puffs in generating repetitive Ca2+ oscillations. EMBO J. 20: 65-76, 2001
Callamaras, N. & Parker, I. Phasic characteristic of elementary Ca2+ release sites underlying quantal responses to IP3. EMBO J. 19: 3608-3617, 2000.
Elementary events of calcium signaling. NIH GM-48071
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