1
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Hamed YMF, Ghosh B, Marshall KL. PIEZO ion channels: force sensors of the interoceptive nervous system. J Physiol 2024. [PMID: 38456626 DOI: 10.1113/jp284077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 02/08/2024] [Indexed: 03/09/2024] Open
Abstract
Many organs are designed to move: the heart pumps each second, the gastrointestinal tract squeezes and churns to digest food, and we contract and relax skeletal muscles to move our bodies. Sensory neurons of the peripheral nervous system detect signals from bodily tissues, including the forces generated by these movements, to control physiology. The processing of these internal signals is called interoception, but this is a broad term that includes a wide variety of both chemical and mechanical sensory processes. Mechanical senses are understudied, but rapid progress has been made in the last decade, thanks in part to the discovery of the mechanosensory PIEZO ion channels (Coste et al., 2010). The role of these mechanosensors within the interoceptive nervous system is the focus of this review. In defining the transduction molecules that govern mechanical interoception, we will have a better grasp of how these signals drive physiology.
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Affiliation(s)
- Yasmeen M F Hamed
- Graduate School of Biomedical Sciences, Baylor College of Medicine, Houston, Texas, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
| | - Britya Ghosh
- Graduate School of Biomedical Sciences, Baylor College of Medicine, Houston, Texas, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
| | - Kara L Marshall
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas, USA
- Howard Hughes Medical Institute, Baylor College of Medicine, Houston, Texas, USA
- Lead contact
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2
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Villarino NW, Hamed YMF, Ghosh B, Dubin AE, Lewis AH, Odem MA, Loud MC, Wang Y, Servin-Vences MR, Patapoutian A, Marshall KL. Labeling PIEZO2 activity in the peripheral nervous system. Neuron 2023; 111:2488-2501.e8. [PMID: 37321223 PMCID: PMC10527906 DOI: 10.1016/j.neuron.2023.05.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 03/24/2023] [Accepted: 05/17/2023] [Indexed: 06/17/2023]
Abstract
Sensory neurons detect mechanical forces from both the environment and internal organs to regulate physiology. PIEZO2 is a mechanosensory ion channel critical for touch, proprioception, and bladder stretch sensation, yet its broad expression in sensory neurons suggests it has undiscovered physiological roles. To fully understand mechanosensory physiology, we must know where and when PIEZO2-expressing neurons detect force. The fluorescent styryl dye FM 1-43 was previously shown to label sensory neurons. Surprisingly, we find that the vast majority of FM 1-43 somatosensory neuron labeling in mice in vivo is dependent on PIEZO2 activity within the peripheral nerve endings. We illustrate the potential of FM 1-43 by using it to identify novel PIEZO2-expressing urethral neurons that are engaged by urination. These data reveal that FM 1-43 is a functional probe for mechanosensitivity via PIEZO2 activation in vivo and will facilitate the characterization of known and novel mechanosensory processes in multiple organ systems.
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Affiliation(s)
- Nicholas W Villarino
- Department of Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA; Howard Hughes Medical Institute, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Yasmeen M F Hamed
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Graduate Program in Development, Disease Models, and Therapeutics, Baylor College of Medicine, Houston, TX 77030
| | - Britya Ghosh
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Adrienne E Dubin
- Department of Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Amanda H Lewis
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Max A Odem
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Meaghan C Loud
- Department of Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA; Howard Hughes Medical Institute, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Yu Wang
- Department of Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - M Rocio Servin-Vences
- Department of Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Ardem Patapoutian
- Department of Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA; Howard Hughes Medical Institute, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | - Kara L Marshall
- Department of Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA; Howard Hughes Medical Institute, The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.
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3
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Servin-Vences MR, Lam RM, Koolen A, Wang Y, Saade DN, Loud M, Kacmaz H, Frausto S, Zhang Y, Beyder A, Marshall KL, Bönnemann CG, Chesler AT, Patapoutian A. PIEZO2 in somatosensory neurons controls gastrointestinal transit. Cell 2023; 186:3386-3399.e15. [PMID: 37541196 PMCID: PMC10501318 DOI: 10.1016/j.cell.2023.07.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 04/24/2023] [Accepted: 07/06/2023] [Indexed: 08/06/2023]
Abstract
The gastrointestinal tract is in a state of constant motion. These movements are tightly regulated by the presence of food and help digestion by mechanically breaking down and propelling gut content. Mechanical sensing in the gut is thought to be essential for regulating motility; however, the identity of the neuronal populations, the molecules involved, and the functional consequences of this sensation are unknown. Here, we show that humans lacking PIEZO2 exhibit impaired bowel sensation and motility. Piezo2 in mouse dorsal root, but not nodose ganglia is required to sense gut content, and this activity slows down food transit rates in the stomach, small intestine, and colon. Indeed, Piezo2 is directly required to detect colon distension in vivo. Our study unveils the mechanosensory mechanisms that regulate the transit of luminal contents throughout the gut, which is a critical process to ensure proper digestion, nutrient absorption, and waste removal.
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Affiliation(s)
- M Rocio Servin-Vences
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Ruby M Lam
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA; NIH-Brown University Graduate Program in Neuroscience, Providence, RI, USA; National Center for Complementary and Integrative Health, National Institutes of Health, Bethesda, MD, USA
| | - Alize Koolen
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Yu Wang
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Dimah N Saade
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Meaghan Loud
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Halil Kacmaz
- Division of Gastroenterology and Hepatology, Enteric Neuroscience Program (ENSP), Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Suzanne Frausto
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Yunxiao Zhang
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Arthur Beyder
- Division of Gastroenterology and Hepatology, Enteric Neuroscience Program (ENSP), Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Kara L Marshall
- Department of Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute, Houston, TX, USA
| | - Carsten G Bönnemann
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Alexander T Chesler
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA; National Center for Complementary and Integrative Health, National Institutes of Health, Bethesda, MD, USA.
| | - Ardem Patapoutian
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, San Diego, CA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA.
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4
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Mulhall EM, Gharpure A, Lee RM, Dubin AE, Aaron JS, Marshall KL, Spencer KR, Reiche MA, Henderson SC, Chew TL, Patapoutian A. Direct observation of the conformational states of PIEZO1. Nature 2023; 620:1117-1125. [PMID: 37587339 PMCID: PMC10468401 DOI: 10.1038/s41586-023-06427-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 07/11/2023] [Indexed: 08/18/2023]
Abstract
PIEZOs are mechanosensitive ion channels that convert force into chemoelectric signals1,2 and have essential roles in diverse physiological settings3. In vitro studies have proposed that PIEZO channels transduce mechanical force through the deformation of extensive blades of transmembrane domains emanating from a central ion-conducting pore4-8. However, little is known about how these channels interact with their native environment and which molecular movements underlie activation. Here we directly observe the conformational dynamics of the blades of individual PIEZO1 molecules in a cell using nanoscopic fluorescence imaging. Compared with previous structural models of PIEZO1, we show that the blades are significantly expanded at rest by the bending stress exerted by the plasma membrane. The degree of expansion varies dramatically along the length of the blade, where decreased binding strength between subdomains can explain increased flexibility of the distal blade. Using chemical and mechanical modulators of PIEZO1, we show that blade expansion and channel activation are correlated. Our findings begin to uncover how PIEZO1 is activated in a native environment. More generally, as we reliably detect conformational shifts of single nanometres from populations of channels, we expect that this approach will serve as a framework for the structural analysis of membrane proteins through nanoscopic imaging.
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Affiliation(s)
- Eric M Mulhall
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA
| | - Anant Gharpure
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA
| | - Rachel M Lee
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA, USA
| | - Adrienne E Dubin
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA
| | - Jesse S Aaron
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA, USA
| | - Kara L Marshall
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Kathryn R Spencer
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA
| | - Michael A Reiche
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA, USA
| | - Scott C Henderson
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
| | - Teng-Leong Chew
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA, USA
| | - Ardem Patapoutian
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA.
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5
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Ma S, Dubin AE, Romero LO, Loud M, Salazar A, Chu S, Klier N, Masri S, Zhang Y, Wang Y, Chesler AT, Wilkinson KA, Vásquez V, Marshall KL, Patapoutian A. Excessive mechanotransduction in sensory neurons causes joint contractures. Science 2023; 379:201-206. [PMID: 36634173 PMCID: PMC10163824 DOI: 10.1126/science.add3598] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Distal arthrogryposis (DA) is a collection of rare disorders that are characterized by congenital joint contractures. Most DA mutations are in muscle- and joint-related genes, and the anatomical defects originate cell-autonomously within the musculoskeletal system. However, gain-of-function mutations in PIEZO2, a principal mechanosensor in somatosensation, cause DA subtype 5 (DA5) through unknown mechanisms. We show that expression of a gain-of-function PIEZO2 mutation in proprioceptive sensory neurons that mainly innervate muscle spindles and tendons is sufficient to induce DA5-like phenotypes in mice. Overactive PIEZO2 causes anatomical defects through increased activity within the peripheral nervous system during postnatal development. Furthermore, botulinum toxin (Botox) and a dietary fatty acid that modulates PIEZO2 activity reduce DA5-like deficits. This reveals a role for somatosensory neurons: Excessive mechanosensation within these neurons disrupts musculoskeletal development.
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Affiliation(s)
- Shang Ma
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA 92037, USA
| | - Adrienne E Dubin
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA 92037, USA
| | - Luis O Romero
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA.,Integrated Biomedical Sciences Graduate Program, College of Graduate Health Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Meaghan Loud
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA 92037, USA
| | - Alexandra Salazar
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA 92037, USA
| | - Sarah Chu
- Department of Biological Sciences, San Jose State University, San Jose, CA, USA
| | - Nikola Klier
- Department of Biological Sciences, San Jose State University, San Jose, CA, USA
| | - Sameer Masri
- Department of Biological Sciences, San Jose State University, San Jose, CA, USA
| | - Yunxiao Zhang
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA 92037, USA
| | - Yu Wang
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA 92037, USA
| | - Alex T Chesler
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.,National Center for Complementary and Integrative Health, National Institutes of Health, Bethesda, MD, USA
| | | | - Valeria Vásquez
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Kara L Marshall
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Ardem Patapoutian
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA 92037, USA
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6
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Murthy SE, Loud MC, Daou I, Marshall KL, Schwaller F, Kühnemund J, Francisco AG, Keenan WT, Dubin AE, Lewin GR, Patapoutian A. The mechanosensitive ion channel Piezo2 mediates sensitivity to mechanical pain in mice. Sci Transl Med 2019; 10:10/462/eaat9897. [PMID: 30305457 DOI: 10.1126/scitranslmed.aat9897] [Citation(s) in RCA: 179] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 09/19/2018] [Indexed: 12/19/2022]
Abstract
The brush of a feather and a pinprick are perceived as distinct sensations because they are detected by discrete cutaneous sensory neurons. Inflammation or nerve injury can disrupt this sensory coding and result in maladaptive pain states, including mechanical allodynia, the development of pain in response to innocuous touch. However, the molecular mechanisms underlying the alteration of mechanical sensitization are poorly understood. In mice and humans, loss of mechanically activated PIEZO2 channels results in the inability to sense discriminative touch. However, the role of Piezo2 in acute and sensitized mechanical pain is not well defined. Here, we showed that optogenetic activation of Piezo2-expressing sensory neurons induced nociception in mice. Mice lacking Piezo2 in caudal sensory neurons had impaired nocifensive responses to mechanical stimuli. Consistently, ex vivo recordings in skin-nerve preparations from these mice showed diminished Aδ-nociceptor and C-fiber firing in response to mechanical stimulation. Punctate and dynamic allodynia in response to capsaicin-induced inflammation and spared nerve injury was absent in Piezo2-deficient mice. These results indicate that Piezo2 mediates inflammation- and nerve injury-induced sensitized mechanical pain, and suggest that targeting PIEZO2 might be an effective strategy for treating mechanical allodynia.
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Affiliation(s)
- Swetha E Murthy
- Howard Hughes Medical Institute, Department of Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Meaghan C Loud
- Howard Hughes Medical Institute, Department of Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Ihab Daou
- Howard Hughes Medical Institute, Department of Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Kara L Marshall
- Howard Hughes Medical Institute, Department of Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Frederick Schwaller
- Department of Neuroscience, Max Delbrück Center for Molecular Medicine, Robert-Rössle Straße 10, Berlin 13125, Germany
| | - Johannes Kühnemund
- Department of Neuroscience, Max Delbrück Center for Molecular Medicine, Robert-Rössle Straße 10, Berlin 13125, Germany
| | - Allain G Francisco
- Howard Hughes Medical Institute, Department of Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - William T Keenan
- Howard Hughes Medical Institute, Department of Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Adrienne E Dubin
- Howard Hughes Medical Institute, Department of Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Gary R Lewin
- Department of Neuroscience, Max Delbrück Center for Molecular Medicine, Robert-Rössle Straße 10, Berlin 13125, Germany.,Excellence Cluster Neurocure, Charité Universitätsmedizin, Berlin 13125, Germany
| | - Ardem Patapoutian
- Howard Hughes Medical Institute, Department of Neuroscience, The Scripps Research Institute, La Jolla, CA 92037, USA.
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7
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Moayedi Y, Greenberg SA, Jenkins BA, Marshall KL, Dimitrov LV, Nelson AM, Owens DM, Lumpkin EA. Camphor white oil induces tumor regression through cytotoxic T cell-dependent mechanisms. Mol Carcinog 2019; 58:722-734. [PMID: 30582219 DOI: 10.1002/mc.22965] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/18/2018] [Accepted: 12/20/2018] [Indexed: 12/11/2022]
Abstract
Bioactive derivatives from the camphor laurel tree, Cinnamomum camphora, are posited to exhibit chemopreventive properties but the efficacy and mechanism of these natural products are not fully understood. We tested an essential-oil derivative, camphor white oil (CWO), for anti-tumor activity in a mouse model of keratinocyte-derived skin cancer. Daily topical treatment with CWO induced dramatic regression of pre-malignant skin tumors and a two-fold reduction in cutaneous squamous cell carcinomas. We next investigated underlying cellular and molecular mechanisms. In cultured keratinocytes, CWO stimulated calcium signaling, resulting in calcineurin-dependent activation of nuclear factor of activated T cells (NFAT). In vivo, CWO induced transcriptional changes in immune-related genes identified by RNA-sequencing, resulting in cytotoxic T cell-dependent tumor regression. Finally, we identified chemical constituents of CWO that recapitulated effects of the admixture. Together, these studies identify T cell-mediated tumor regression as a mechanism through which a plant-derived essential oil diminishes established tumor burden.
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Affiliation(s)
- Yalda Moayedi
- Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, New York
| | - Sophie A Greenberg
- Department of Dermatology, Columbia University Irving Medical Center, New York, New York
| | - Blair A Jenkins
- Medical Scientist Training Program, Columbia University Irving Medical Center, New York, New York
| | - Kara L Marshall
- Department of Dermatology, Columbia University Irving Medical Center, New York, New York
| | - Lina V Dimitrov
- Program in Neuroscience and Behavior, Barnard College, Columbia University, New York, New York
| | - Aislyn M Nelson
- Department of Dermatology, Columbia University Irving Medical Center, New York, New York.,Department of Neuroscience, Baylor College of Medicine, Houston, Texas
| | - David M Owens
- Department of Dermatology, Columbia University Irving Medical Center, New York, New York.,Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York
| | - Ellen A Lumpkin
- Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, New York.,Department of Dermatology, Columbia University Irving Medical Center, New York, New York
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8
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Zeng WZ, Marshall KL, Min S, Daou I, Chapleau MW, Abboud FM, Liberles SD, Patapoutian A. PIEZOs mediate neuronal sensing of blood pressure and the baroreceptor reflex. Science 2018; 362:464-467. [PMID: 30361375 DOI: 10.1126/science.aau6324] [Citation(s) in RCA: 251] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 09/07/2018] [Indexed: 12/22/2022]
Abstract
Activation of stretch-sensitive baroreceptor neurons exerts acute control over heart rate and blood pressure. Although this homeostatic baroreflex has been described for more than 80 years, the molecular identity of baroreceptor mechanosensitivity remains unknown. We discovered that mechanically activated ion channels PIEZO1 and PIEZO2 are together required for baroreception. Genetic ablation of both Piezo1 and Piezo2 in the nodose and petrosal sensory ganglia of mice abolished drug-induced baroreflex and aortic depressor nerve activity. Awake, behaving animals that lack Piezos had labile hypertension and increased blood pressure variability, consistent with phenotypes in baroreceptor-denervated animals and humans with baroreflex failure. Optogenetic activation of Piezo2-positive sensory afferents was sufficient to initiate baroreflex in mice. These findings suggest that PIEZO1 and PIEZO2 are the long-sought baroreceptor mechanosensors critical for acute blood pressure control.
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Affiliation(s)
- Wei-Zheng Zeng
- Howard Hughes Medical Institute, Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Kara L Marshall
- Howard Hughes Medical Institute, Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Soohong Min
- Howard Hughes Medical Institute, Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Ihab Daou
- Howard Hughes Medical Institute, Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Mark W Chapleau
- Abboud Cardiovascular Research Center, Department of Internal Medicine and Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.,Veterans Affairs Medical Center, Iowa City, IA 52242, USA
| | - Francois M Abboud
- Abboud Cardiovascular Research Center, Department of Internal Medicine and Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Stephen D Liberles
- Howard Hughes Medical Institute, Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Ardem Patapoutian
- Howard Hughes Medical Institute, Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA.
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9
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Marshall KL, Clary RC, Baba Y, Orlowsky RL, Gerling GJ, Lumpkin EA. Touch Receptors Undergo Rapid Remodeling in Healthy Skin. Cell Rep 2017; 17:1719-1727. [PMID: 27829143 DOI: 10.1016/j.celrep.2016.10.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 09/21/2016] [Accepted: 10/12/2016] [Indexed: 11/24/2022] Open
Abstract
Sensory tissues exposed to the environment, such as skin, olfactory epithelia, and taste buds, continuously renew; therefore, peripheral neurons must have mechanisms to maintain appropriate innervation patterns. Although somatosensory neurons regenerate after injury, little is known about how these neurons cope with normal target organ changes. To elucidate neuronal plasticity in healthy skin, we analyzed the structure of Merkel-cell afferents, which are gentle touch receptors, during skin remodeling that accompanies mouse hair-follicle regeneration. The number of Merkel cells is reduced by 90% and axonal arbors are simplified during active hair growth. These structures rebound within just days. Computational modeling predicts that Merkel-cell changes are probabilistic, but myelinated branch stability depends on Merkel-cell inputs. Electrophysiology and behavior demonstrate that tactile responsiveness is less reliable during active growth than in resting skin. These results reveal that somatosensory neurons display structural plasticity at the cost of impairment in the reliability of encoding gentle touch.
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Affiliation(s)
- Kara L Marshall
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA; Integrated Training Program in Cellular, Molecular and Biomedical Sciences, Columbia University, New York, NY 10032, USA
| | - Rachel C Clary
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA; Neurobiology and Behavior Training Program, Columbia University, New York, NY 10032, USA
| | - Yoshichika Baba
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA
| | - Rachel L Orlowsky
- Department of Systems and Information Engineering, University of Virginia, Charlottesville, VA 22904, USA; Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22904, USA
| | - Gregory J Gerling
- Department of Systems and Information Engineering, University of Virginia, Charlottesville, VA 22904, USA; Department of Biomedical Engineering, University of Virginia, Charlottesville, VA 22904, USA
| | - Ellen A Lumpkin
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA; Integrated Training Program in Cellular, Molecular and Biomedical Sciences, Columbia University, New York, NY 10032, USA; Neurobiology and Behavior Training Program, Columbia University, New York, NY 10032, USA; Department of Dermatology, Columbia University, New York, NY 10032, USA.
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10
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Sterbing-D'Angelo SJ, Chadha M, Marshall KL, Moss CF. Functional role of airflow-sensing hairs on the bat wing. J Neurophysiol 2016; 117:705-712. [PMID: 27852729 DOI: 10.1152/jn.00261.2016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 11/15/2016] [Indexed: 11/22/2022] Open
Abstract
The wing membrane of the big brown bat (Eptesicus fuscus) is covered by a sparse grid of microscopic hairs. We showed previously that various tactile receptors (e.g., lanceolate endings and Merkel cell neurite complexes) are associated with wing-hair follicles. Furthermore, we found that depilation of these hairs decreased the maneuverability of bats in flight. In the present study, we investigated whether somatosensory signals arising from the hairs carry information about airflow parameters. Neural responses to calibrated air puffs on the wing were recorded from primary somatosensory cortex of E. fuscus Single units showed sparse, phasic, and consistently timed spikes that were insensitive to air-puff duration and magnitude. The neurons discriminated airflow from different directions, and a majority responded with highest firing rates to reverse airflow from the trailing toward the leading edge of the dorsal wing. Reverse airflow, caused by vortices, occurs commonly in slowly flying bats. Hence, the present findings suggest that cortical neurons are specialized to monitor reverse airflow, indicating laminar airflow disruption (vorticity) that potentially destabilizes flight and leads to stall. NEW & NOTEWORTHY Bat wings are adaptive airfoils that enable demanding flight maneuvers. The bat wing is sparsely covered with sensory hairs, and wing-hair removal results in reduced flight maneuverability. Here, we report for the first time single-neuron responses recorded from primary somatosensory cortex to airflow stimulation that varied in amplitude, duration, and direction. The neurons show high sensitivity to the directionality of airflow and might act as stall detectors.
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Affiliation(s)
- S J Sterbing-D'Angelo
- Institute for Systems Research, University of Maryland, College Park, Maryland; .,Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, Maryland; and
| | - M Chadha
- Program in Neuroscience and Cognitive Science, University of Maryland, College Park, Maryland.,Department of Psychology, University of Maryland, College Park, Maryland.,Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, Maryland; and
| | - K L Marshall
- Departments of Dermatology and Physiology and Cellular Biophysics, Columbia University, New York, New York
| | - C F Moss
- Institute for Systems Research, University of Maryland, College Park, Maryland.,Program in Neuroscience and Cognitive Science, University of Maryland, College Park, Maryland.,Department of Psychology, University of Maryland, College Park, Maryland.,Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, Maryland; and
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11
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Salzman S, Romanofsky HJ, West G, Marshall KL, Jacobs SD, Lambropoulos JC. Acidic magnetorheological finishing of infrared polycrystalline materials. Appl Opt 2016; 55:8448-8456. [PMID: 27828155 DOI: 10.1364/ao.55.008448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Chemical-vapor-deposited (CVD) ZnS is an example of a polycrystalline material that is difficult to polish smoothly via the magnetorheological finishing (MRF) technique. When MRF-polished, the internal infrastructure of the material tends to manifest on the surface as millimeter-sized "pebbles," and the surface roughness observed is considerably high. The fluid's parameters important to developing a magnetorheological (MR) fluid that is capable of polishing CVD ZnS smoothly were previously discussed and presented. These parameters were acidic pH (∼4.5) and low viscosity (∼47 cP). MRF with such a unique MR fluid was shown to reduce surface artifacts in the form of pebbles; however, surface microroughness was still relatively high because of the absence of a polishing abrasive in the formulation. In this study, we examine the effect of two polishing abrasives-alumina and nanodiamond-on the surface finish of several CVD ZnS substrates, and on other important IR polycrystalline materials that were finished with acidic MR fluids containing these two polishing abrasives. Surface microroughness results obtained were as low as ∼28 nm peak-to-valley and ∼6-nm root mean square.
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12
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Rutkauskas M, Farrell C, Dorrer C, Marshall KL, Lundquist TR, Vedagarbha P, Reid DT. High-resolution subsurface microscopy of CMOS integrated circuits using radially polarized light. Opt Lett 2015; 40:5502-5505. [PMID: 26625036 DOI: 10.1364/ol.40.005502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Under high numerical aperture (NA) conditions, a linearly polarized plane wave focuses to a spot that is extended along the E-field vector, but radially polarized light is predicted to form a circular spot whose diameter equals the narrower dimension obtained with linear polarization. This effect provides an opportunity for improved resolution in high-NA microscopy, and here we present a performance study of subsurface two-photon optical-beam-induced current solid-immersion-lens microscopy of a complementary metal-oxide semiconductor integrated circuit, showing a resolution improvement by using radially polarized illumination. By comparing images of the same structural features we show that radial polarization achieves a resolution of 126 nm, while linear polarization achieves resolutions of 122 and 165 nm, depending on the E-field orientation. These results are consistent with the theoretically expected behavior and are supported by high-resolution images which show superior feature definition using radial polarization.
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13
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Marshall KL, Chadha M, deSouza LA, Sterbing-D'Angelo SJ, Moss CF, Lumpkin EA. Somatosensory substrates of flight control in bats. Cell Rep 2015; 11:851-858. [PMID: 25937277 DOI: 10.1016/j.celrep.2015.04.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 03/11/2015] [Accepted: 03/29/2015] [Indexed: 10/23/2022] Open
Abstract
Flight maneuvers require rapid sensory integration to generate adaptive motor output. Bats achieve remarkable agility with modified forelimbs that serve as airfoils while retaining capacity for object manipulation. Wing sensory inputs provide behaviorally relevant information to guide flight; however, components of wing sensory-motor circuits have not been analyzed. Here, we elucidate the organization of wing innervation in an insectivore, the big brown bat, Eptesicus fuscus. We demonstrate that wing sensory innervation differs from other vertebrate forelimbs, revealing a peripheral basis for the atypical topographic organization reported for bat somatosensory nuclei. Furthermore, the wing is innervated by an unusual complement of sensory neurons poised to report airflow and touch. Finally, we report that cortical neurons encode tactile and airflow inputs with sparse activity patterns. Together, our findings identify neural substrates of somatosensation in the bat wing and imply that evolutionary pressures giving rise to mammalian flight led to unusual sensorimotor projections.
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Affiliation(s)
- Kara L Marshall
- Departments of Dermatology and Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA
| | - Mohit Chadha
- Program in Neuroscience and Cognitive Science, University of Maryland, College Park, MD 20742, USA; Department of Psychology, University of Maryland, College Park, MD 20742, USA
| | - Laura A deSouza
- Program in Neurobiology and Behavior, Columbia University, New York, NY 10032, USA
| | | | - Cynthia F Moss
- Program in Neuroscience and Cognitive Science, University of Maryland, College Park, MD 20742, USA; Department of Psychology, University of Maryland, College Park, MD 20742, USA; Institute for Systems Research, University of Maryland, College Park, MD 20742, USA.
| | - Ellen A Lumpkin
- Departments of Dermatology and Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA; Program in Neurobiology and Behavior, Columbia University, New York, NY 10032, USA.
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14
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Wang Y, Marshall KL, Baba Y, Lumpkin EA, Gerling GJ. Compressive viscoelasticity of freshly excised mouse skin is dependent on specimen thickness, strain level and rate. PLoS One 2015; 10:e0120897. [PMID: 25803703 PMCID: PMC4372409 DOI: 10.1371/journal.pone.0120897] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 01/27/2015] [Indexed: 11/18/2022] Open
Abstract
Although the skin’s mechanical properties are well characterized in tension, little work has been done in compression. Here, the viscoelastic properties of a population of mouse skin specimens (139 samples from 36 mice, aged 5 to 34 weeks) were characterized upon varying specimen thickness, as well as strain level and rate. Over the population, we observed the skin’s viscoelasticity to be quite variable, yet found systematic correlation of residual stress ratio with skin thickness and strain, and of relaxation time constants with strain rates. In particular, as specimen thickness ranged from 211 to 671 μm, we observed significant variation in both quasi-linear viscoelasticity (QLV) parameters, the relaxation time constant (τ1 = 0.19 ± 0.10 s) and steady-state residual stress ratio (G∞ = 0.28 ± 0.13). Moreover, when τ1 was decoupled and fixed, we observed that G∞ positively correlated with skin thickness. Second, as steady-state stretch was increased (λ∞ from 0.22 to 0.81), we observed significant variation in both QLV parameters (τ1 = 0.26 ± 0.14 s, G∞ = 0.47 ± 0.17), and when τ1 was fixed, G∞ positively correlated with stretch level. Third, as strain rate was increased from 0.06 to 22.88 s−1, the median time constant τ1 varied from 1.90 to 0.31 s, and thereby negatively correlated with strain rate. These findings indicate that the natural range of specimen thickness, as well as experimental controls of compression level and rate, significantly influence measurements of skin viscoelasticity.
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Affiliation(s)
- Yuxiang Wang
- Department of Systems and Information Engineering, University of Virginia, 151 Engineers Way, Charlottesville, Virginia, 22903, United States of America
- Department of Mechanical and Aerospace Engineering, University of Virginia, 122 Engineers Way, Charlottesville, Virginia, 22903, United States of America
| | - Kara L. Marshall
- Department of Dermatology, Columbia University College of Physicians & Surgeons, 1150 St. Nicholas Ave., New York, New York, 10032, United States of America
| | - Yoshichika Baba
- Department of Dermatology, Columbia University College of Physicians & Surgeons, 1150 St. Nicholas Ave., New York, New York, 10032, United States of America
| | - Ellen A. Lumpkin
- Department of Dermatology, Columbia University College of Physicians & Surgeons, 1150 St. Nicholas Ave., New York, New York, 10032, United States of America
- Department of Physiology & Cellular Biophysics, Columbia University College of Physicians & Surgeons, 1150 St. Nicholas Ave., New York, New York, 10032, United States of America
| | - Gregory J. Gerling
- Department of Systems and Information Engineering, University of Virginia, 151 Engineers Way, Charlottesville, Virginia, 22903, United States of America
- Department of Biomedical Engineering, University of Virginia, 415 Lane Road, Charlottesville, Virginia, 22908, United States of America
- * E-mail:
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15
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Glebov VY, Forrest CJ, Marshall KL, Romanofsky M, Sangster TC, Shoup MJ, Stoeckl C. A new neutron time-of-flight detector for fuel-areal-density measurements on OMEGA. Rev Sci Instrum 2014; 85:11E102. [PMID: 25430281 DOI: 10.1063/1.4886428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A new neutron time-of-flight (nTOF) detector for fuel-areal-density measurements in cryogenic DT implosions was installed on the OMEGA Laser System. The nTOF detector has a cylindrical thin-wall, stainless-steel, 8-in.-diam, 4-in.-thick cavity filled with an oxygenated liquid xylene scintillator. Four gated photomultiplier tubes (PMTs) with different gains are used to measure primary DT and D2 neutrons, down-scattered neutrons in nT and nD kinematic edge regions, and to study tertiary neutrons in the same detector. The nTOF detector is located 13.4 m from target chamber center in a well-collimated line of sight. The design details of the nTOF detector, PMT optimization, and test results on OMEGA will be presented.
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Affiliation(s)
- V Yu Glebov
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - C J Forrest
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - K L Marshall
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - M Romanofsky
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - T C Sangster
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - M J Shoup
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
| | - C Stoeckl
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
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16
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Maksimovic S, Nakatani M, Baba Y, Nelson AM, Marshall KL, Wellnitz SA, Firozi P, Woo SH, Ranade S, Patapoutian A, Lumpkin EA. Epidermal Merkel cells are mechanosensory cells that tune mammalian touch receptors. Nature 2014; 509:617-21. [PMID: 24717432 PMCID: PMC4097312 DOI: 10.1038/nature13250] [Citation(s) in RCA: 347] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 03/13/2014] [Indexed: 11/18/2022]
Abstract
Touch submodalities, such as flutter and pressure, are mediated by somatosensory afferents whose terminal specializations extract tactile features and encode them as action potential trains with unique activity patterns. Whether non-neuronal cells tune touch receptors through active or passive mechanisms is debated. Terminal specializations are thought to function as passive mechanical filters analogous to the cochlea's basilar membrane, which deconstructs complex sounds into tones that are transduced by mechanosensory hair cells. The model that cutaneous specializations are merely passive has been recently challenged because epidermal cells express sensory ion channels and neurotransmitters; however, direct evidence that epidermal cells excite tactile afferents is lacking. Epidermal Merkel cells display features of sensory receptor cells and make 'synapse-like' contacts with slowly adapting type I (SAI) afferents. These complexes, which encode spatial features such as edges and texture, localize to skin regions with high tactile acuity, including whisker follicles, fingertips and touch domes. Here we show that Merkel cells actively participate in touch reception in mice. Merkel cells display fast, touch-evoked mechanotransduction currents. Optogenetic approaches in intact skin show that Merkel cells are both necessary and sufficient for sustained action-potential firing in tactile afferents. Recordings from touch-dome afferents lacking Merkel cells demonstrate that Merkel cells confer high-frequency responses to dynamic stimuli and enable sustained firing. These data are the first, to our knowledge, to directly demonstrate a functional, excitatory connection between epidermal cells and sensory neurons. Together, these findings indicate that Merkel cells actively tune mechanosensory responses to facilitate high spatio-temporal acuity. Moreover, our results indicate a division of labour in the Merkel cell-neurite complex: Merkel cells signal static stimuli, such as pressure, whereas sensory afferents transduce dynamic stimuli, such as moving gratings. Thus, the Merkel cell-neurite complex is an unique sensory structure composed of two different receptor cell types specialized for distinct elements of discriminative touch.
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Affiliation(s)
| | - Masashi Nakatani
- Department of Dermatology, Columbia University, New York, NY 10032
- Graduate School of System Design and Management, Keio University, Yokohama, JP
| | - Yoshichika Baba
- Department of Dermatology, Columbia University, New York, NY 10032
| | - Aislyn M. Nelson
- Department of Dermatology, Columbia University, New York, NY 10032
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77006
| | - Kara L. Marshall
- Department of Dermatology, Columbia University, New York, NY 10032
| | - Scott A. Wellnitz
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77006
| | - Pervez Firozi
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77006
| | - Seung-Hyun Woo
- Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, The Scripps Research Institute, La Jolla CA 92037 USA
| | - Sanjeev Ranade
- Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, The Scripps Research Institute, La Jolla CA 92037 USA
| | - Ardem Patapoutian
- Howard Hughes Medical Institute, Molecular and Cellular Neuroscience, The Scripps Research Institute, La Jolla CA 92037 USA
- Genomic Institute of the Novartis Research Foundation, San Diego, CA 92121 USA
| | - Ellen A. Lumpkin
- Department of Dermatology, Columbia University, New York, NY 10032
- Program in Neurobiology & Behavior, Columbia University, New York, NY 10032
- Department of Physiology & Cellular Biophysics, Columbia University, New York, NY 10032 USA
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17
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Lesniak DR, Marshall KL, Wellnitz SA, Jenkins BA, Baba Y, Rasband MN, Gerling GJ, Lumpkin EA. Computation identifies structural features that govern neuronal firing properties in slowly adapting touch receptors. eLife 2014; 3:e01488. [PMID: 24448409 PMCID: PMC3896213 DOI: 10.7554/elife.01488] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Touch is encoded by cutaneous sensory neurons with diverse morphologies and physiological outputs. How neuronal architecture influences response properties is unknown. To elucidate the origin of firing patterns in branched mechanoreceptors, we combined neuroanatomy, electrophysiology and computation to analyze mouse slowly adapting type I (SAI) afferents. These vertebrate touch receptors, which innervate Merkel cells, encode shape and texture. SAI afferents displayed a high degree of variability in touch-evoked firing and peripheral anatomy. The functional consequence of differences in anatomical architecture was tested by constructing network models representing sequential steps of mechanosensory encoding: skin displacement at touch receptors, mechanotransduction and action-potential initiation. A systematic survey of arbor configurations predicted that the arrangement of mechanotransduction sites at heminodes is a key structural feature that accounts in part for an afferent’s firing properties. These findings identify an anatomical correlate and plausible mechanism to explain the driver effect first described by Adrian and Zotterman. DOI:http://dx.doi.org/10.7554/eLife.01488.001 Sensory receptors in the skin supply us with information about objects in the world around us, including their shape and texture. These receptors also detect pressure, temperature, and pain, enabling us to respond appropriately to stimuli that could be potentially harmful. The activation of a touch receptor—for example, due to the movement of a hair—causes ions to flow into the cell, changing the electric charge inside it. When the charge exceeds a threshold value, the cell fires action potentials, which travel along its axon to the central nervous system. The patterns of these action potentials from a population of touch receptors carry all the information about a touch stimulus to the brain. Different types of sensory receptors have unique anatomical structures and distinct signaling patterns; however, little is known about how the structures of sensory receptors influence action potential firing. Now Lesniak and Marshall et al. have revealed that structure determines function in a type of mammalian touch receptor called the slowly adapting type I receptor, which is concentrated in fingertips and other areas of high tactile acuity. With the aid of high-resolution microscopy, the complex branching structure of the receptor and its network of nerve endings were mapped in three dimensions. Experiments revealed highly variable structures and firing patterns between individual touch receptors, and computational modeling showed that changing either the number or the arrangement of receptor endings influenced the neuron’s firing properties. This is the first computational model that captures touch encoding by combining skin properties, sensory transduction, and spike initiation. As well as providing new information on how structure permits function, this work opens up new possibilities for exploring how the skin maintains its sensory capabilities during routine maintenance and after injury. DOI:http://dx.doi.org/10.7554/eLife.01488.002
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Affiliation(s)
- Daine R Lesniak
- Department of Systems and Information Engineering, University of Virginia, Charlottesville, United States
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18
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Abstract
The skin is a dynamic organ whose complex material properties are capable of withstanding continuous mechanical stress while accommodating insults and organism growth. Moreover, synchronized hair cycles, comprising waves of hair growth, regression and rest, are accompanied by dramatic fluctuations in skin thickness in mice. Whether such structural changes alter skin mechanics is unknown. Mouse models are extensively used to study skin biology and pathophysiology, including aging, UV-induced skin damage and somatosensory signaling. As the skin serves a pivotal role in the transfer function from sensory stimuli to neuronal signaling, we sought to define the mechanical properties of mouse skin over a range of normal physiological states. Skin thickness, stiffness and modulus were quantitatively surveyed in adult, female mice (Mus musculus). These measures were analyzed under uniaxial compression, which is relevant for touch reception and compression injuries, rather than tension, which is typically used to analyze skin mechanics. Compression tests were performed with 105 full-thickness, freshly isolated specimens from the hairy skin of the hind limb. Physiological variables included body weight, hair-cycle stage, maturity level, skin site and individual animal differences. Skin thickness and stiffness were dominated by hair-cycle stage at young (6–10 weeks) and intermediate (13–19 weeks) adult ages but by body weight in mature mice (26–34 weeks). Interestingly, stiffness varied inversely with thickness so that hyperelastic modulus was consistent across hair-cycle stages and body weights. By contrast, the mechanics of hairy skin differs markedly with anatomical location. In particular, skin containing fascial structures such as nerves and blood vessels showed significantly greater modulus than adjacent sites. Collectively, this systematic survey indicates that, although its structure changes dramatically throughout adult life, mouse skin at a given location maintains a constant elastic modulus to compression throughout normal physiological stages.
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Affiliation(s)
- Yuxiang Wang
- Department of Systems and Information Engineering, University of Virginia, Charlottesville, Virginia, United States of America
| | - Kara L. Marshall
- Department of Dermatology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
| | - Yoshichika Baba
- Department of Dermatology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
| | - Gregory J. Gerling
- Department of Systems and Information Engineering, University of Virginia, Charlottesville, Virginia, United States of America
- * E-mail: (GJG); (EAL)
| | - Ellen A. Lumpkin
- Department of Dermatology, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
- Department of Physiology and Cellular Biophysics, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
- * E-mail: (GJG); (EAL)
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19
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Wang Y, Marshall KL, Baba Y, Lumpkin EA, Gerling GJ. Natural Variation in Skin Thickness Argues for Mechanical Stimulus Control by Force Instead of Displacement. Joint Eurohaptics Conf Symp Haptic Interfaces Virtual Environ Teleoper Syst 2013; 2013:645-650. [PMID: 24500653 DOI: 10.1109/whc.2013.6548484] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The neural response to touch stimuli is influenced by skin properties as well as the delivery of stimuli. Here, we compare stimuli controlled by displacement and force, and analyze the impact on firing rates of slowly adapting type I afferents as skin thickness and elasticity change. Uniaxial compression tests were used to measure the mechanical properties of mouse hind limb skin (n=5), resulting in a range of skin thickness measurements (211.6-530.6 μm) and hyper- and visco-elastic properties (average coefficient of variation=0.27).Values were integrated to an axisymmetric finite element model using an Ogden strain energy function. This calculated the propagation of surface loads to tactile end-organ locations, where maximum compressive stress and its rate were sampled and linearly regressed to firing rate. For the observed range of skin thickness, firing response was predicted under both force and displacement control of a ramp-and-hold stimulus. Over the ramp phase of stimulation, the variance in predicted firing rate was higher under displacement than under force control (22.2versus 4.9 Hz) with a similar trend in the sustained phase of stimulation (4.6versus1.3Hz). Given that skin thickness varies significantly between specimens, for human skin perhaps seven more so than for mice, the use of force control is predicted to decrease experimental variance in neurophysiological and psychophysical responses.
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Affiliation(s)
- Yuxiang Wang
- Department of Systems and Information Engineering, University of Virginia
| | - Kara L Marshall
- Dept. of Dermatology, Columbia University College of Physicians & Surgeons
| | - Yoshichika Baba
- Dept. of Physiology & Cellular Biophysics, Columbia University College of Physicians & Surgeons
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20
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Abstract
Multiple senses, including hearing, touch and osmotic regulation, require the ability to convert force into an electrical signal: A process called mechanotransduction. Mechanotransduction occurs through specialized proteins that open an ion channel pore in response to a mechanical stimulus. Many of these proteins remain unidentified in vertebrates, but known mechanotransduction channels in lower organisms provide clues into their identity and mechanism. Bacteria, fruit flies and nematodes have all been used to elucidate the molecules necessary for force transduction. This chapter discusses many different mechanical senses and takes an evolutionary approach to review the proteins responsible for mechanotransduction in various biological kingdoms.
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Affiliation(s)
- Kara L. Marshall
- Integrated Graduate Program in Cellular, Molecular, Structural and Genetic Studies, Columbia University College of Physicians & Surgeons, New York, NY 10032
| | - Ellen A. Lumpkin
- Departments of Dermatology and Physiology and Cellular Biophysics, Columbia University College of Physicians & Surgeons, New York, NY 10032
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21
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Abstract
Degenerin/epithelial sodium channels (DEG/ENaCs) are luminaries of gentle touch in Caenorhabditis elegans. In this issue of Neuron, Geffeney et al. demonstrate that eponymous DEG-1 channels carry mechanotransduction currents in a polymodal neuron, where they act upstream of transient receptor potential (TRP) channels.
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Affiliation(s)
- Aislyn M Nelson
- Department of Dermatology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
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Dorrer C, Wei SKH, Leung P, Vargas M, Wegman K, Boulé J, Zhao Z, Marshall KL, Chen SH. High-damage-threshold static laser beam shaping using optically patterned liquid-crystal devices. Opt Lett 2011; 36:4035-4037. [PMID: 22002377 DOI: 10.1364/ol.36.004035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Beam shaping of coherent laser beams is demonstrated using liquid crystal (LC) cells with optically patterned pixels. The twist angle of a nematic LC is locally set to either 0 or 90° by an alignment layer prepared via exposure to polarized UV light. The two distinct pixel types induce either no polarization rotation or a 90° polarization rotation, respectively, on a linearly polarized optical field. An LC device placed between polarizers functions as a binary transmission beam shaper with a highly improved damage threshold compared to metal beam shapers. Using a coumarin-based photoalignment layer, various devices have been fabricated and tested, with a measured single-shot nanosecond damage threshold higher than 30 J/cm2.
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Affiliation(s)
- C Dorrer
- Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299, USA.
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23
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Abstract
The sense of touch detects forces that bombard the body's surface. In metazoans, an assortment of morphologically and functionally distinct mechanosensory cell types are tuned to selectively respond to diverse mechanical stimuli, such as vibration, stretch, and pressure. A comparative evolutionary approach across mechanosensory cell types and genetically tractable species is beginning to uncover the cellular logic of touch reception.
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Affiliation(s)
- Ellen A Lumpkin
- Department of Dermatology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
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Glebov VY, Sangster TC, Stoeckl C, Knauer JP, Theobald W, Marshall KL, Shoup MJ, Buczek T, Cruz M, Duffy T, Romanofsky M, Fox M, Pruyne A, Moran MJ, Lerche RA, McNaney J, Kilkenny JD, Eckart MJ, Schneider D, Munro D, Stoeffl W, Zacharias R, Haslam JJ, Clancy T, Yeoman M, Warwas D, Horsfield CJ, Bourgade JL, Landoas O, Disdier L, Chandler GA, Leeper RJ. The National Ignition Facility neutron time-of-flight system and its initial performance (invited). Rev Sci Instrum 2010; 81:10D325. [PMID: 21033848 DOI: 10.1063/1.3492351] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The National Ignition Facility (NIF) successfully completed its first inertial confinement fusion (ICF) campaign in 2009. A neutron time-of-flight (nTOF) system was part of the nuclear diagnostics used in this campaign. The nTOF technique has been used for decades on ICF facilities to infer the ion temperature of hot deuterium (D(2)) and deuterium-tritium (DT) plasmas based on the temporal Doppler broadening of the primary neutron peak. Once calibrated for absolute neutron sensitivity, the nTOF detectors can be used to measure the yield with high accuracy. The NIF nTOF system is designed to measure neutron yield and ion temperature over 11 orders of magnitude (from 10(8) to 10(19)), neutron bang time in DT implosions between 10(12) and 10(16), and to infer areal density for DT yields above 10(12). During the 2009 campaign, the three most sensitive neutron time-of-flight detectors were installed and used to measure the primary neutron yield and ion temperature from 25 high-convergence implosions using D(2) fuel. The OMEGA yield calibration of these detectors was successfully transferred to the NIF.
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Affiliation(s)
- V Yu Glebov
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA.
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Watson TM, Marshall KL, Kay BH. Colonization and laboratory biology of Aedes notoscriptus from Brisbane, Australia. J Am Mosq Control Assoc 2000; 16:138-142. [PMID: 10901637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Methods are described for the laboratory colonization of Aedes notoscriptus from Brisbane, Queensland, Australia. To initiate colonization, efforts were made to duplicate the natural environment of this species, including the use of a bromeliad as a swarm marker and oviposition substrate. The colony stabilized after the F8 with eclosion rates >50%, and an average production of 5,220 adults since the F9. The fecundity of Ae. notoscriptus averaged 29.4+/-10.5 eggs (range 14-57). The average development times from egg hatch to adult were 11 and 20 days under typical summer (20.5-28.9 degrees C) and winter (10.1-21.2 degrees C) conditions in Brisbane, respectively. This is the 1st published report of the colonization of Ae. notoscriptus.
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Affiliation(s)
- T M Watson
- Queensland Institute of Medical Research and University of Queensland, Tropical Health Program, PO Royal Brisbane Hospital, Australia
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Hutin YJ, Bell BP, Marshall KL, Schaben CP, Dart M, Quinlisk MP, Shapiro CN. Identifying target groups for a potential vaccination program during a hepatitis A communitywide outbreak. Am J Public Health 1999; 89:918-21. [PMID: 10358687 PMCID: PMC1508638 DOI: 10.2105/ajph.89.6.918] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES This study sought to identify groups for targeted vaccination during a communitywide hepatitis A outbreak in 1996. METHODS Residents of the Sioux City, Iowa, metropolitan area reported with hepatitis A between September 1995 and August 1996 were sampled and compared with population-based controls. RESULTS In comparison with 51 controls, the 40 case patients were more likely to inject methamphetamine, to attend emergency rooms more often than other health care facilities, and to have a family member who used the Special Supplemental Nutrition Program for Women, Infants, and Children. CONCLUSIONS Groups at increased risk of hepatitis A can be identified that might be [corrected] accessed for vaccination during communitywide outbreaks.
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Affiliation(s)
- Y J Hutin
- Hepatitis Branch, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
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Marshall KL, Haddock J, Bickel N, Singel D, Jacobs SD. Angular-scattering characteristics of ferroelectric liquid-crystal electro-optical devices operating in the transient-scattering and the extended-scattering modes. Appl Opt 1999; 38:1287-1294. [PMID: 18305744 DOI: 10.1364/ao.38.001287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The angular distribution of forward-scattered light in transient-scattering-mode (TSM) and extended-scattering-mode (ESM) ferroelectric liquid-crystal (FLC) devices was evaluated by use of circularly polarized incident light. For both modes the intensity and the distribution of forward-scattered light depended primarily on the FLC birefringence, spontaneous polarization, and the cell path length. In the FLC materials examined, the forward-scattering intensity under ESM drive conditions increased with longer FLC pitch lengths, whereas under TSM conditions stronger forward scattering was observed with increasing FLC spontaneous polarization. Although both TSM and ESM drive conditions displayed a similar angular distribution for forward-scattered light, the intensity of ESM scattering over a 0 degrees -6 degrees range was considerably smaller than that observed in earlier experiments with linearly polarized incident light.
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Affiliation(s)
- K L Marshall
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1212, USA.
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Busico KM, Marshall KL, Ksiazek TG, Roels TH, Fleerackers Y, Feldmann H, Khan AS, Peters CJ. Prevalence of IgG antibodies to Ebola virus in individuals during an Ebola outbreak, Democratic Republic of the Congo, 1995. J Infect Dis 1999; 179 Suppl 1:S102-7. [PMID: 9988172 DOI: 10.1086/514309] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
During the 1995 outbreak of Ebola (EBO) hemorrhagic fever in Kikwit, Democratic Republic of Congo, two surveys using a new ELISA for EBO (subtype Zaire) virus antigen were conducted to assess the prevalence of EBO IgG antibodies among residents of Kikwit and the surrounding area. The first study determined the proportion of antibody-positive individuals who were self-identified forest and city workers from the Kikwit area. Serum samples from 9 (2.2%) of 414 workers had IgG EBO antibodies. The second study determined the proportion of EBO antibody-positive individuals who lived in villages surrounding Kikwit. The prevalence of IgG EBO antibodies in this population was 9.3% (151161). The difference in the overall prevalence of EBO antibodies may indicate that villagers have a greater chance of exposure to EBO virus compared with those living in and in close proximity to cities.
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Affiliation(s)
- K M Busico
- Special Pathogens Branch, Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA
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Marshall KL, Vogt RL. Illness associated with eating seaweed, Hawaii, 1994. West J Med 1998; 169:293-5. [PMID: 9830364 PMCID: PMC1305326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Affiliation(s)
- K L Marshall
- Epidemic Intelligence Service State Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
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Abstract
The objective of this study was to estimate the true incidence of acute cases of hepatitis B (HB) in Hawaii in 1993 and thus determine the sensitivity of reporting to the Hawaii Department of Health (HDOH). The study found that the relatively low HB incidence rate of 1.6 per 100,000 reported in Hawaii in 1992 is probably, at least in part, due to underreporting by laboratories and to reporting requirements that are inadequate for accurate classification of acute cases.
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Zuber PL, Binkin NJ, Ignacio AC, Marshall KL, Tribble SP, Tipple MA, Vogt RL. Tuberculosis screening for immigrants and refugees. Diagnostic outcomes in the state of Hawaii. Am J Respir Crit Care Med 1996; 154:151-5. [PMID: 8680671 DOI: 10.1164/ajrccm.154.1.8680671] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The effectiveness of the required overseas tuberculosis (TB) screening for immigrants and refugees to the United States has not been evaluated since new guidelines were introduced in 1991. Using data from the Hawaii State TB register for 1992-1993, patient records, and data from the U.S. government notifications of suspect TB among aliens, we determined the percentage of persons either classified as having active TB (B1), inactive TB (B2), or considered "normal" overseas, who were evaluated and subsequently diagnosed with active TB within 1 yr of arrival in the United States. Of the 124 TB cases among immigrants and refugees evaluated within 1 yr of arrival, 78 (63%) had been classified overseas as B1, 17 (14%) as B2, and 29 (23%) as "normal." The proportion of TB cases diagnosed after arrival in the United States was 14.0% for B1s and 2.1% for B2s. This proportion decreased with increasing age. A positive skin test was a strong predictor (OR: 10.7; 95% CI: 1.4-80.1) of culture-confirmed TB. These data document that immigrants and refugees with B1 and B2 TB status have a high prevalence of active TB. They should be promptly evaluated after arrival in the United States to determine the need for curative or preventive therapy.
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Affiliation(s)
- P L Zuber
- Division of Tuberculosis Elimination, National Center for HIV, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA
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Korenic EM, Marshall KL. Blending polysiloxane glass resins to produce optical films with a specific refractive index. Appl Opt 1995; 34:8048-8049. [PMID: 21068903 DOI: 10.1364/ao.34.008048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Commercially available polysiloxane resins can be blended either in the solid state or in solution to produce optically transparent films whose refractive index is a linear function of the weight percent of one component. Useful applications for these "glass resins" include protective coatings for hydroscopic optical crystals, antireflective or index-matching films, and homeotropic alignment layers for liquid crystal devices.
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Marshall KL, Jacobs SD, Miller JE. Midinfrared modulation through the use of field-induced scattering in ferroelectric liquid crystals. Appl Opt 1995; 34:6704-6713. [PMID: 21060525 DOI: 10.1364/ao.34.006704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The feasibility of the use of modulation devices based on field-induced transient scattering in ferroelectric liquid crystals (LC) to replace mechanical choppers used in uncooled infrared-imaging systems was investigated. Devices fabricated with ITO-coated ZnSe substrates and a ferroelectric LC path length of 25 µm were able to modulate optical radiation by transient forward scattering at rates approaching 20 kHz. Through the use of a commercial arbitrary waveform generator and associated PC-based software, drive waveforms were developed that produced a variable, square-wave optical-modulation pattern by the extension of the duration of the scattering state to periods ranging from hundreds of microseconds to milliseconds. The ability of these extended-scattering-mode (ESM) devices to modulate radiation in both the visible and midinfrared regions was verified in a simple experiment through the use of a Fourier-transform infrared spectrometer, in which an unoptimized ESM device displayed a 40% modulation dep th for IR radiation in the 8-12-µm region.
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Abstract
The reaction of some 5-acylaminopyrimidines, having 4-oxo groups, with phosphorus oxychloride or phosphorus pentasulfide leads to the oxazolo- or thiazolo -[5,4-d] pyrimidines respectively. The condensation of amidinothiourea with pentane-2,4-dione leads to 1-(4,6-dimethylpyrimidin-2-yl)urea directly, and subsequent reaction with diethyl acetylene- dicarboxylate gives a thiazolylaminopyrimidine . The synthesis of some other pyrimidinylureas and thioureas has also been carried out.
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