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Forman TE, Sajek MP, Larson ED, Mukherjee N, Fantauzzo KA. PDGFRα signaling regulates Srsf3 transcript binding to affect PI3K signaling and endosomal trafficking. bioRxiv 2024:2024.04.03.587975. [PMID: 38617350 PMCID: PMC11014628 DOI: 10.1101/2024.04.03.587975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
Signaling through the platelet-derived growth factor receptor alpha (PDGFRa) plays a critical role in craniofacial development, as mutations in PDGFRA are associated with cleft lip/palate in humans and Pdgfra mutant mouse models display varying degrees of facial clefting. Phosphatidylinositol 3-kinase (PI3K)/Akt is the primary effector of PDGFRα signaling during skeletal development in the mouse. We previously demonstrated that Akt phosphorylates the RNA-binding protein serine/arginine-rich splicing factor 3 (Srsf3) downstream of PI3K-mediated PDGFRa signaling in mouse embryonic palatal mesenchyme (MEPM) cells, leading to its nuclear translocation. We further showed that ablation of Srsf3 in the murine neural crest lineage results in severe midline facial clefting, due to defects in proliferation and survival of cranial neural crest cells, and widespread alternative RNA splicing (AS) changes. Here, we sought to determine the molecular mechanisms by which Srsf3 activity is regulated downstream of PDGFRa signaling to control AS of transcripts necessary for craniofacial development. We demonstrated via enhanced UV-crosslinking and immunoprecipitation (eCLIP) of MEPM cells that PDGF-AA stimulation leads to preferential binding of Srsf3 to exons and loss of binding to canonical Srsf3 CA-rich motifs. Through the analysis of complementary RNA-seq data, we showed that Srsf3 activity results in the preferential inclusion of exons with increased GC content and lower intron to exon length ratio. Moreover, we found that the subset of transcripts that are bound by Srsf3 and undergo AS upon PDGFRα signaling commonly encode regulators of PI3K signaling and early endosomal trafficking. Functional validation studies further confirmed that Srsf3 activity downstream of PDGFRα signaling leads to retention of the receptor in early endosomes and increases in downstream PI3K-mediated Akt signaling. Taken together, our findings reveal that growth factor-mediated phosphorylation of an RNA-binding protein underlies gene expression regulation necessary for mammalian craniofacial development.
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Affiliation(s)
- Thomas E. Forman
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Medical Scientist Training Program, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Marcin P. Sajek
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland
| | - Eric D. Larson
- Department of Otolaryngology – Head and Neck Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Basic and Translational Sciences, Penn Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Neelanjan Mukherjee
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Katherine A. Fantauzzo
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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2
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Campaña MB, Perkins MR, McCabe MC, Neumann A, Larson ED, Fantauzzo KA. PDGFRα/β heterodimer activation negatively affects downstream ERK1/2 signaling and cellular proliferation. bioRxiv 2023:2023.12.27.573428. [PMID: 38234806 PMCID: PMC10793460 DOI: 10.1101/2023.12.27.573428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
The platelet-derived growth factor receptor (PDGFR) family of receptor tyrosine kinases allows cells to communicate with one another by binding to growth factors at the plasma membrane and activating intracellular signaling pathways to elicit responses such as migration, proliferation, survival and differentiation. The PDGFR family consists of two receptors, PDGFRα and PDGFRβ, that dimerize to form PDGFRα homodimers, PDGFRα/β heterodimers and PDGFRβ homodimers. Here, we overcame prior technical limitations in visualizing and purifying PDGFRα/β heterodimers by generating a cell line stably expressing C-terminal fusions of PDGFRα and PDGFRβ with bimolecular fluorescence complementation fragments corresponding to the N-terminal and C-terminal regions of the Venus fluorescent protein, respectively. We found that these receptors heterodimerize relatively quickly in response to PDGF-BB ligand treatment, with a peak of receptor autophosphorylation following 5 minutes of ligand stimulation. Moreover, we demonstrated that PDGFRα/β heterodimers are rapidly internalized into early endosomes, particularly signaling endosomes, where they dwell for extended lengths of time. We showed that PDGFRα/β heterodimer activation does not induce downstream phosphorylation of ERK1/2 and significantly inhibits cell proliferation. Further, we characterized the PDGFR dimer-specific interactome and identified MYO1D as a novel protein that preferentially binds PDGFRα/β heterodimers. We demonstrated that knockdown of MYO1D leads to retention of PDGFRα/β heterodimers at the plasma membrane, resulting in increased phosphorylation of ERK1/2 and increased cell proliferation. Collectively, our findings impart valuable insight into the molecular mechanisms by which specificity is introduced downstream of PDGFR activation to differentially propagate signaling and generate distinct cellular responses.
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Affiliation(s)
- Maria B. Campaña
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Madison R. Perkins
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Maxwell C. McCabe
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Andrew Neumann
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Eric D. Larson
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Katherine A. Fantauzzo
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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3
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Cheng F, Luo H, Jenkins JD, Larson ED. Impacts of the Inflation Reduction Act on the Economics of Clean Hydrogen and Synthetic Liquid Fuels. Environ Sci Technol 2023; 57:15336-15347. [PMID: 37647613 DOI: 10.1021/acs.est.3c03063] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
The Inflation Reduction Act (IRA) in the United States provides unprecedented incentives for deploying low-carbon hydrogen and liquid fuels, among other low-greenhouse gas (GHG) emissions technologies. To better understand the prospective competitiveness of low-carbon or negative-carbon hydrogen and liquid fuels under the IRA in the early 2030s, we examined the impacts of the IRA provisions on the costs of producing hydrogen and synthetic liquid fuel made from natural gas, electricity, short-cycle biomass (agricultural residues), and corn-derived ethanol. We determined that, with IRA credits (45V or 45Q) but excluding the incentives provided by other national or state policies, hydrogen produced by electrolysis using carbon-free electricity (green H2) and by natural gas reforming with carbon capture and storage (CCS) (blue H2) is cost-competitive with the carbon-intensive benchmark gray H2, which is produced by steam methane reforming. Biomass-derived H2 with or without CCS is not cost-competitive under the current IRA provisions. However, if the IRA allowed biomass gasification with CCS to claim a 45V credit for carbon-neutral H2 and a 45Q credit for negative biogenic CO2 emissions, this pathway would be less costly than gray H2. The IRA credit for clean fuels (45Z), currently stipulated to end in 2027, would need to be extended or similar policy support would need to be provided by other national or state policies in order for clean synthetic liquid fuel to be cost-competitive with petroleum-derived liquid fuels. The levelized IRA subsidies per unit of CO2 mitigated for all of the hydrogen and synthetic liquid fuel production pathways, except for electricity-derived synthetic liquid fuel, range from $65-$384/t of CO2. These values are within or below the range of the U.S. federal government's estimates of the social cost of carbon (SCC) in the 2030-2040 time frame.
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Affiliation(s)
- Fangwei Cheng
- Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| | - Hongxi Luo
- Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
| | - Jesse D Jenkins
- Andlinger Center for Energy and the Environment, Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Eric D Larson
- Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey 08544, United States
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Shechtman LA, Scott JK, Larson ED, Isner TJ, Johnson BJ, Gaillard D, Dempsey PJ, Barlow LA. High Sox2 expression predicts taste lineage competency of lingual progenitors in vitro. Development 2023; 150:dev201375. [PMID: 36794954 PMCID: PMC10112921 DOI: 10.1242/dev.201375] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 10/17/2022] [Accepted: 01/19/2023] [Indexed: 02/17/2023]
Abstract
Taste buds on the tongue contain taste receptor cells (TRCs) that detect sweet, sour, salty, umami and bitter stimuli. Like non-taste lingual epithelium, TRCs are renewed from basal keratinocytes, many of which express the transcription factor SOX2. Genetic lineage tracing has shown that SOX2+ lingual progenitors give rise to both taste and non-taste lingual epithelium in the posterior circumvallate taste papilla (CVP) of mice. However, SOX2 is variably expressed among CVP epithelial cells, suggesting that their progenitor potential may vary. Using transcriptome analysis and organoid technology, we show that cells expressing SOX2 at higher levels are taste-competent progenitors that give rise to organoids comprising both TRCs and lingual epithelium. Conversely, organoids derived from progenitors that express SOX2 at lower levels are composed entirely of non-taste cells. Hedgehog and WNT/β-catenin are required for taste homeostasis in adult mice. However, manipulation of hedgehog signaling in organoids has no impact on TRC differentiation or progenitor proliferation. By contrast, WNT/β-catenin promotes TRC differentiation in vitro in organoids derived from higher but not low SOX2+ expressing progenitors.
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Affiliation(s)
- Lauren A. Shechtman
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Jennifer K. Scott
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Eric D. Larson
- Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Department of Otolaryngology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Trevor J. Isner
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Cell Biology, Stem Cells and Development Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Bryan J. Johnson
- Cell Biology, Stem Cells and Development Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Dany Gaillard
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Peter J. Dempsey
- Cell Biology, Stem Cells and Development Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Section of Developmental Biology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Linda A. Barlow
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Cell Biology, Stem Cells and Development Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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5
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Zhang C, Yang H, Zhao Y, Ma L, Larson ED, Greig C. Realizing ambitions: A framework for iteratively assessing and communicating national decarbonization progress. iScience 2022; 25:103695. [PMID: 35036878 PMCID: PMC8749441 DOI: 10.1016/j.isci.2021.103695] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 12/04/2022] Open
Abstract
A growing number of governments are pledging to achieve net-zero greenhouse gas emissions by mid-century. Despite such ambitions, realized emissions reductions continue to fall alarmingly short of modeled energy transition pathways for achieving net-zero. This gap is largely a result of the difficulty of realistically modeling all the techno-economic and sociopolitical capabilities that are required to deliver actual emissions reductions. This limitation of models suggests the need for an energy-systems analytical framework that goes well beyond energy-system modeling in order to close the gap between ambition and reality. Toward that end, we propose the Emissions-Sustainability-Governance-Operation (ESGO) framework for structured assessment and transparent communication of national capabilities and realization. We illustrate the critical role of energy modeling in ESGO using recent net-zero modeling studies for the world's two largest emitters, China and the United States. This illustration leads to recommendations for improvements to energy-system modeling to enable more productive ESGO implementation.
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Affiliation(s)
- Chuan Zhang
- Energy Systems Analysis Group, Andlinger Center for Energy and the Environment, Princeton University, Princeton, NJ 08544, USA
| | - Honghua Yang
- State Key Laboratory of Power Systems, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China
| | - Yunlong Zhao
- State Key Laboratory of Power Systems, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China
| | - Linwei Ma
- State Key Laboratory of Power Systems, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China
- Corresponding author
| | - Eric D. Larson
- Energy Systems Analysis Group, Andlinger Center for Energy and the Environment, Princeton University, Princeton, NJ 08544, USA
- Corresponding author
| | - Chris Greig
- Energy Systems Analysis Group, Andlinger Center for Energy and the Environment, Princeton University, Princeton, NJ 08544, USA
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6
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Elling CL, Scholes MA, Streubel SO, Larson ED, Wine TM, Bootpetch TC, Yoon PJ, Kofonow JM, Gubbels SP, Cass SP, Robertson CE, Jenkins HA, Prager JD, Frank DN, Chan KH, Friedman NR, Ryan AF, Santos-Cortez RLP. The FUT2 Variant c.461G>A (p.Trp154*) Is Associated With Differentially Expressed Genes and Nasopharyngeal Microbiota Shifts in Patients With Otitis Media. Front Cell Infect Microbiol 2022; 11:798246. [PMID: 35096646 PMCID: PMC8798324 DOI: 10.3389/fcimb.2021.798246] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 12/20/2021] [Indexed: 12/30/2022] Open
Abstract
Otitis media (OM) is a leading cause of childhood hearing loss. Variants in FUT2, which encodes alpha-(1,2)-fucosyltransferase, were identified to increase susceptibility to OM, potentially through shifts in the middle ear (ME) or nasopharyngeal (NP) microbiotas as mediated by transcriptional changes. Greater knowledge of differences in relative abundance of otopathogens in carriers of pathogenic variants can help determine risk for OM in patients. In order to determine the downstream effects of FUT2 variation, we examined gene expression in relation to carriage of a common pathogenic FUT2 c.461G>A (p.Trp154*) variant using RNA-sequence data from saliva samples from 28 patients with OM. Differential gene expression was also examined in bulk mRNA and single-cell RNA-sequence data from wildtype mouse ME mucosa after inoculation with non-typeable Haemophilus influenzae (NTHi). In addition, microbiotas were profiled from ME and NP samples of 65 OM patients using 16S rRNA gene sequencing. In human carriers of the FUT2 variant, FN1, KMT2D, MUC16 and NBPF20 were downregulated while MTAP was upregulated. Post-infectious expression in the mouse ME recapitulated these transcriptional differences, with the exception of Fn1 upregulation after NTHi-inoculation. In the NP, Candidate Division TM7 was associated with wildtype genotype (FDR-adj-p=0.009). Overall, the FUT2 c.461G>A variant was associated with transcriptional changes in processes related to response to infection and with increased load of potential otopathogens in the ME and decreased commensals in the NP. These findings provide increased understanding of how FUT2 variants influence gene transcription and the mucosal microbiota, and thus contribute to the pathology of OM.
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Affiliation(s)
- Christina L. Elling
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Human Medical Genetics and Genomics Program, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Melissa A. Scholes
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Pediatric Otolaryngology, Children’s Hospital Colorado, Aurora, CO, United States
| | - Sven-Olrik Streubel
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Pediatric Otolaryngology, Children’s Hospital Colorado, Aurora, CO, United States
| | - Eric D. Larson
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Todd M. Wine
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Pediatric Otolaryngology, Children’s Hospital Colorado, Aurora, CO, United States
| | - Tori C. Bootpetch
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Patricia J. Yoon
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Pediatric Otolaryngology, Children’s Hospital Colorado, Aurora, CO, United States
| | - Jennifer M. Kofonow
- Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Samuel P. Gubbels
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Stephen P. Cass
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Charles E. Robertson
- Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Herman A. Jenkins
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Jeremy D. Prager
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Pediatric Otolaryngology, Children’s Hospital Colorado, Aurora, CO, United States
| | - Daniel N. Frank
- Division of Infectious Diseases, Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Kenny H. Chan
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Pediatric Otolaryngology, Children’s Hospital Colorado, Aurora, CO, United States
| | - Norman R. Friedman
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Pediatric Otolaryngology, Children’s Hospital Colorado, Aurora, CO, United States
| | - Allen F. Ryan
- Division of Otolaryngology, Department of Surgery, San Diego School of Medicine and Veterans Affairs Medical Center, University of California, La Jolla, CA, United States
| | - Regie Lyn P. Santos-Cortez
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Human Medical Genetics and Genomics Program, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Center for Children’s Surgery, Children’s Hospital Colorado, Aurora, CO, United States
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Butera IM, Larson ED, DeFreese AJ, Lee AKC, Gifford RH, Wallace MT. Functional localization of audiovisual speech using near infrared spectroscopy. Brain Topogr 2022; 35:416-430. [PMID: 35821542 PMCID: PMC9334437 DOI: 10.1007/s10548-022-00904-1] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 05/19/2022] [Indexed: 11/21/2022]
Abstract
Visual cues are especially vital for hearing impaired individuals such as cochlear implant (CI) users to understand speech in noise. Functional Near Infrared Spectroscopy (fNIRS) is a light-based imaging technology that is ideally suited for measuring the brain activity of CI users due to its compatibility with both the ferromagnetic and electrical components of these implants. In a preliminary step toward better elucidating the behavioral and neural correlates of audiovisual (AV) speech integration in CI users, we designed a speech-in-noise task and measured the extent to which 24 normal hearing individuals could integrate the audio of spoken monosyllabic words with the corresponding visual signals of a female speaker. In our behavioral task, we found that audiovisual pairings provided average improvements of 103% and 197% over auditory-alone listening conditions in -6 and -9 dB signal-to-noise ratios consisting of multi-talker background noise. In an fNIRS task using similar stimuli, we measured activity during auditory-only listening, visual-only lipreading, and AV listening conditions. We identified cortical activity in all three conditions over regions of middle and superior temporal cortex typically associated with speech processing and audiovisual integration. In addition, three channels active during the lipreading condition showed uncorrected correlations associated with behavioral measures of audiovisual gain as well as with the McGurk effect. Further work focusing primarily on the regions of interest identified in this study could test how AV speech integration may differ for CI users who rely on this mechanism for daily communication.
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Affiliation(s)
- Iliza M. Butera
- grid.152326.10000 0001 2264 7217Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN USA
| | - Eric D. Larson
- grid.34477.330000000122986657Institute for Learning & Brain Sciences, University of Washington, Seattle Washington, USA
| | - Andrea J. DeFreese
- grid.152326.10000 0001 2264 7217Department of Hearing and Speech Sciences, Vanderbilt University, Nashville, TN USA
| | - Adrian KC Lee
- grid.34477.330000000122986657Institute for Learning & Brain Sciences, University of Washington, Seattle Washington, USA ,grid.34477.330000000122986657Department of Speech and Hearing Sciences, University of Washington, Seattle, Washington USA
| | - René H. Gifford
- grid.152326.10000 0001 2264 7217Department of Hearing and Speech Sciences, Vanderbilt University, Nashville, TN USA
| | - Mark T. Wallace
- grid.152326.10000 0001 2264 7217Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN USA ,grid.152326.10000 0001 2264 7217Department of Hearing and Speech Sciences, Vanderbilt University, Nashville, TN USA ,grid.412807.80000 0004 1936 9916Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN USA
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8
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Dennison BJC, Larson ED, Fu R, Mo J, Fantauzzo KA. Srsf3 mediates alternative RNA splicing downstream of PDGFRα signaling in the facial mesenchyme. Development 2021; 148:269256. [PMID: 34184034 DOI: 10.1242/dev.199448] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [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: 01/18/2021] [Accepted: 06/10/2021] [Indexed: 12/13/2022]
Abstract
Signaling through the platelet-derived growth factor receptor alpha (PDGFRα) is crucial for mammalian craniofacial development, although the mechanisms by which the activity of downstream intracellular effectors is regulated to mediate gene expression changes have not been defined. We find that the RNA-binding protein Srsf3 is phosphorylated at Akt consensus sites downstream of PI3K-mediated PDGFRα signaling in mouse palatal mesenchyme cells, leading to its nuclear translocation. We further demonstrate that ablation of Srsf3 in the mouse neural crest lineage leads to facial clefting due to defective cranial neural crest cell proliferation and survival. Finally, we show that Srsf3 regulates the alternative RNA splicing of transcripts encoding protein kinases in the mouse facial process mesenchyme to regulate PDGFRα-dependent intracellular signaling. Collectively, our findings reveal that alternative RNA splicing is an important mechanism of gene expression regulation downstream of PI3K/Akt-mediated PDGFRα signaling in the facial mesenchyme and identify Srsf3 as a critical regulator of craniofacial development.
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Affiliation(s)
- Brenna J C Dennison
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.,RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Eric D Larson
- Department of Otolaryngology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Rui Fu
- RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Julia Mo
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Katherine A Fantauzzo
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.,RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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9
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Golden EJ, Larson ED, Shechtman LA, Trahan GD, Gaillard D, Fellin TJ, Scott JK, Jones KL, Barlow LA. Onset of taste bud cell renewal starts at birth and coincides with a shift in SHH function. eLife 2021; 10:64013. [PMID: 34009125 PMCID: PMC8172241 DOI: 10.7554/elife.64013] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [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] [Received: 10/14/2020] [Accepted: 05/18/2021] [Indexed: 12/12/2022] Open
Abstract
Embryonic taste bud primordia are specified as taste placodes on the tongue surface and differentiate into the first taste receptor cells (TRCs) at birth. Throughout adult life, TRCs are continually regenerated from epithelial progenitors. Sonic hedgehog (SHH) signaling regulates TRC development and renewal, repressing taste fate embryonically, but promoting TRC differentiation in adults. Here, using mouse models, we show TRC renewal initiates at birth and coincides with onset of SHHs pro-taste function. Using transcriptional profiling to explore molecular regulators of renewal, we identified Foxa1 and Foxa2 as potential SHH target genes in lingual progenitors at birth and show that SHH overexpression in vivo alters FoxA1 and FoxA2 expression relevant to taste buds. We further bioinformatically identify genes relevant to cell adhesion and cell locomotion likely regulated by FOXA1;FOXA2 and show that expression of these candidates is also altered by forced SHH expression. We present a new model where SHH promotes TRC differentiation by regulating changes in epithelial cell adhesion and migration.
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Affiliation(s)
- Erin J Golden
- Department of Cell & Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, United States.,The Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, United States
| | - Eric D Larson
- The Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, United States.,Department of Otolaryngology, University of Colorado Anschutz Medical Campus, Aurora, United States
| | - Lauren A Shechtman
- Department of Cell & Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, United States.,The Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, United States
| | - G Devon Trahan
- Department of Pediatrics, Section of Hematology, Oncology, and Bone Marrow Transplant, University of Colorado Anschutz Medical Campus, Aurora, United States
| | - Dany Gaillard
- Department of Cell & Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, United States.,The Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, United States
| | - Timothy J Fellin
- Department of Cell & Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, United States.,The Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, United States
| | - Jennifer K Scott
- Department of Cell & Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, United States.,The Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, United States
| | - Kenneth L Jones
- Department of Pediatrics, Section of Hematology, Oncology, and Bone Marrow Transplant, University of Colorado Anschutz Medical Campus, Aurora, United States
| | - Linda A Barlow
- Department of Cell & Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, United States.,The Rocky Mountain Taste and Smell Center, University of Colorado Anschutz Medical Campus, Aurora, United States
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10
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Baxter BD, Larson ED, Merle L, Feinstein P, Polese AG, Bubak AN, Niemeyer CS, Hassell J, Shepherd D, Ramakrishnan VR, Nagel MA, Restrepo D. Transcriptional profiling reveals potential involvement of microvillous TRPM5-expressing cells in viral infection of the olfactory epithelium. BMC Genomics 2021; 22:224. [PMID: 33781205 PMCID: PMC8007386 DOI: 10.1186/s12864-021-07528-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [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] [Received: 06/08/2020] [Accepted: 03/12/2021] [Indexed: 02/07/2023] Open
Abstract
Background Understanding viral infection of the olfactory epithelium is essential because the olfactory nerve is an important route of entry for viruses to the central nervous system. Specialized chemosensory epithelial cells that express the transient receptor potential cation channel subfamily M member 5 (TRPM5) are found throughout the airways and intestinal epithelium and are involved in responses to viral infection. Results Herein we performed deep transcriptional profiling of olfactory epithelial cells sorted by flow cytometry based on the expression of mCherry as a marker for olfactory sensory neurons and for eGFP in OMP-H2B::mCherry/TRPM5-eGFP transgenic mice (Mus musculus). We find profuse expression of transcripts involved in inflammation, immunity and viral infection in TRPM5-expressing microvillous cells compared to olfactory sensory neurons. Conclusion Our study provides new insights into a potential role for TRPM5-expressing microvillous cells in viral infection of the olfactory epithelium. We find that, as found for solitary chemosensory cells (SCCs) and brush cells in the airway epithelium, and for tuft cells in the intestine, the transcriptome of TRPM5-expressing microvillous cells indicates that they are likely involved in the inflammatory response elicited by viral infection of the olfactory epithelium. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07528-y.
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Affiliation(s)
- B Dnate' Baxter
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.,Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Eric D Larson
- Department of Otolaryngology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Laetitia Merle
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.,Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Paul Feinstein
- The Graduate Center Biochemistry, Biology and CUNY-Neuroscience-Collaborative Programs and Biological Sciences Department, Hunter College, City University of New York, New York, NY, 10065, USA
| | - Arianna Gentile Polese
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.,Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Andrew N Bubak
- Department of Neurology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Christy S Niemeyer
- Department of Neurology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - James Hassell
- Department of Neurology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Doug Shepherd
- Department of Pharmacology, University of Colorado Anschutz Medical Campus and Center for Biological Physics and Department of Physics, Arizona State University, Tempe, USA
| | - Vijay R Ramakrishnan
- Department of Otolaryngology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Maria A Nagel
- Department of Neurology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Diego Restrepo
- Neuroscience Graduate Program, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA. .,Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA.
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11
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Abstract
In taste buds, Type I cells represent the majority of cells (50-60%) and primarily have a glial-like function in taste buds. However, recent studies suggest that they have additional sensory and signaling functions including amiloride-sensitive salt transduction, oxytocin modulation of taste, and substance P mediated GABA release. Nonetheless, the overall function of Type I cells in transduction and signaling remains unclear, primarily because of the lack of a reliable reporter for this cell type. GAD65 expression is specific to Type I taste cells and GAD65 has been used as a Cre driver to study Type I cells in salt taste transduction. To test the specificity of transgene-driven expression, we crossed GAD65Cre mice with floxed tdTomato and Channelrhodopsin (ChR2) lines and examined the progeny with immunochemistry, chorda tympani recording, and calcium imaging. We report that while many tdTomato+ taste cells express NTPDase2, a specific marker of Type I cells, we see some expression of tdTomato in both Gustducin and SNAP25-positive taste cells. We also see ChR2 in cells just outside the fungiform taste buds. Chorda tympani recordings in the GAD65Cre/ChR2 mice show large responses to blue light. Furthermore, several isolated tdTomato-positive taste cells responded to KCl depolarization with increases in intracellular calcium, indicating the presence of voltage-gated calcium channels. Taken together, these data suggest that GAD65Cre mice drive expression in multiple taste cell types and thus cannot be considered a reliable reporter of Type I cell function.
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Affiliation(s)
- Eric D Larson
- Department of Otolaryngology, University of Colorado Anschutz Medical Campus and Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | - Aurelie Vandenbeuch
- Department of Otolaryngology, University of Colorado Anschutz Medical Campus and Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | - Catherine B Anderson
- Department of Otolaryngology, University of Colorado Anschutz Medical Campus and Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | - Sue C Kinnamon
- Department of Otolaryngology, University of Colorado Anschutz Medical Campus and Rocky Mountain Taste and Smell Center, Aurora, CO, USA
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12
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Bosseler AN, Clarke M, Tavabi K, Larson ED, Hippe DS, Taulu S, Kuhl PK. Using magnetoencephalography to examine word recognition, lateralization, and future language skills in 14-month-old infants. Dev Cogn Neurosci 2020; 47:100901. [PMID: 33360832 PMCID: PMC7773883 DOI: 10.1016/j.dcn.2020.100901] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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] [Received: 06/07/2020] [Revised: 12/08/2020] [Accepted: 12/16/2020] [Indexed: 11/15/2022] Open
Abstract
Word learning is a significant milestone in language acquisition. The second year of life marks a period of dramatic advances in infants' expressive and receptive word-processing abilities. Studies show that in adulthood, language processing is left-hemisphere dominant. However, adults learning a second language activate right-hemisphere brain functions. In infancy, acquisition of a first language involves recruitment of bilateral brain networks, and strong left-hemisphere dominance emerges by the third year. In the current study we focus on 14-month-old infants in the earliest stages of word learning using infant magnetoencephalography (MEG) brain imagining to characterize neural activity in response to familiar and unfamiliar words. Specifically, we examine the relationship between right-hemisphere brain responses and prospective measures of vocabulary growth. As expected, MEG source modeling revealed a broadly distributed network in frontal, temporal and parietal cortex that distinguished word classes between 150-900 ms after word onset. Importantly, brain activity in the right frontal cortex in response to familiar words was highly correlated with vocabulary growth at 18, 21, 24, and 27 months. Specifically, higher activation to familiar words in the 150-300 ms interval was associated with faster vocabulary growth, reflecting processing efficiency, whereas higher activation to familiar words in the 600-900 ms interval was associated with slower vocabulary growth, reflecting cognitive effort. These findings inform research and theory on the involvement of right frontal cortex in specific cognitive processes and individual differences related to attention that may play an important role in the development of left-lateralized word processing.
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Affiliation(s)
- Alexis N Bosseler
- Institute for Learning & Brain Sciences, University of Washington, Box 357988, Seattle, WA, 98195, USA.
| | - Maggie Clarke
- Institute for Learning & Brain Sciences, University of Washington, Box 357988, Seattle, WA, 98195, USA
| | - Kambiz Tavabi
- Institute for Learning & Brain Sciences, University of Washington, Box 357988, Seattle, WA, 98195, USA
| | - Eric D Larson
- Institute for Learning & Brain Sciences, University of Washington, Box 357988, Seattle, WA, 98195, USA
| | - Daniel S Hippe
- Department of Radiology, University of Washington, Box 354755, Seattle, WA, 98195, USA
| | - Samu Taulu
- Institute for Learning & Brain Sciences, University of Washington, Box 357988, Seattle, WA, 98195, USA; Department of Physics, University of Washington, Box 351560, Seattle, WA, 98195, USA
| | - Patricia K Kuhl
- Institute for Learning & Brain Sciences, University of Washington, Box 357988, Seattle, WA, 98195, USA; Department of Speech and Hearing Sciences, University of Washington, Box 354875, Seattle, WA, 98195, USA
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13
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Baxter BD, Larson ED, Merle L, Feinstein P, Polese AG, Bubak AN, Niemeyer CS, Hassell J, Shepherd D, Ramakrishnan VR, Nagel MA, Restrepo D. Transcriptional profiling reveals potential involvement of microvillous TRPM5-expressing cells in viral infection of the olfactory epithelium. bioRxiv 2020. [PMID: 32511400 DOI: 10.1101/2020.05.14.096016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Background Understanding viral infection of the olfactory epithelium is essential because the olfactory nerve is an important route of entry for viruses to the central nervous system. Specialized chemosensory epithelial cells that express the transient receptor potential cation channel subfamily M member 5 (TRPM5) are found throughout the airways and intestinal epithelium and are involved in responses to viral infection. Results Herein we performed deep transcriptional profiling of olfactory epithelial cells sorted by flow cytometry based on the expression of mCherry as a marker for olfactory sensory neurons and for eGFP in OMP-H2B::mCherry/TRPM5-eGFP transgenic mice ( Mus musculus ). We find profuse expression of transcripts involved in inflammation, immunity and viral infection in TRPM5-expressing microvillous cells. Conclusion Our study provides new insights into a potential role for TRPM5-expressing microvillous cells in viral infection of the olfactory epithelium. We find that, as found for solitary chemosensory cells (SCCs) and brush cells in the airway epithelium, and for tuft cells in the intestine, the transcriptome of TRPM5-expressing microvillous cells indicates that they are likely involved in the inflammatory response elicited by viral infection of the olfactory epithelium.
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14
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Kennel C, Gould EA, Larson ED, Salcedo E, Vickery T, Restrepo D, Ramakrishnan VR. Differential Expression of Mucins in Murine Olfactory Versus Respiratory Epithelium. Chem Senses 2020; 44:511-521. [PMID: 31300812 DOI: 10.1093/chemse/bjz046] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Mucins are a key component of the surface mucus overlying airway epithelium. Given the different functions of the olfactory and respiratory epithelia, we hypothesized that mucins would be differentially expressed between these 2 areas. Secondarily, we evaluated for potential changes in mucin expression with radiation exposure, given the clinical observations of nasal dryness, altered mucus rheology, and smell loss in radiated patients. Immunofluorescence staining was performed to evaluate expression of mucins 1, 2, 5AC, and 5B in nasal respiratory and olfactory epithelia of control mice and 1 week after exposure to 8 Gy of radiation. Mucins 1, 5AC, and 5B exhibited differential expression patterns between olfactory and respiratory epithelium (RE) while mucin 2 showed no difference. In the olfactory epithelium (OE), mucin 1 was located in a lattice-like pattern around gaps corresponding to dendritic knobs of olfactory sensory neurons, whereas in RE it was intermittently expressed by surface goblet cells. Mucin 5AC was expressed by subepithelial glands in both epithelial types but to a higher degree in the OE. Mucin 5B was expressed by submucosal glands in OE and by surface epithelial cells in RE. At 1-week after exposure to single-dose 8 Gy of radiation, no qualitative effects were seen on mucin expression. Our findings demonstrate that murine OE and RE express mucins differently, and characteristic patterns of mucins 1, 5AC, and 5B can be used to define the underlying epithelium. Radiation (8 Gy) does not appear to affect mucin expression at 1 week. LEVEL OF EVIDENCE N/A (Basic Science Research).IACUC-approved study [Protocol 200065].
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Affiliation(s)
- Christopher Kennel
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Elizabeth A Gould
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, CO, USA.,Neuroscience Program, University of Colorado School of Medicine, Aurora, CO, USA
| | - Eric D Larson
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Ernesto Salcedo
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Thad Vickery
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Diego Restrepo
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, CO, USA.,Neuroscience Program, University of Colorado School of Medicine, Aurora, CO, USA
| | - Vijay R Ramakrishnan
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, CO, USA.,Department of Neurosurgery, University of Colorado School of Medicine, Aurora, CO, USA
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15
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Chen J, Larson ED, Anderson CB, Agarwal P, Frank DN, Kinnamon SC, Ramakrishnan VR. Expression of Bitter Taste Receptors and Solitary Chemosensory Cell Markers in the Human Sinonasal Cavity. Chem Senses 2020; 44:483-495. [PMID: 31231752 DOI: 10.1093/chemse/bjz042] [Citation(s) in RCA: 12] [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] [Indexed: 01/20/2023] Open
Abstract
Some bitter taste receptors (TAS2R gene products) are expressed in the human sinonasal cavity and may function to detect airborne irritants. The expression of all 25 human bitter taste receptors and their location within the upper airway is not yet clear. The aim of this study is to characterize the presence and distribution of TAS2R transcripts and solitary chemosensory cells (SCCs) in different locations of the human sinonasal cavity. Biopsies were obtained from human subjects at up to 4 different sinonasal anatomic sites. PCR, microarray, and qRT-PCR were used to examine gene transcript expression. The 25 human bitter taste receptors as well as the sweet/umami receptor subunit, TAS1R3, and canonical taste signaling effectors are expressed in sinonasal tissue. All 25 human bitter taste receptors are expressed in the human upper airway, and expression of these gene products was higher in the ethmoid sinus than nasal cavity locations. Fluorescent in situ hybridization demonstrates that epithelial TRPM5 and TAS2R38 are expressed in a rare cell population compared with multiciliated cells, and at times, consistent with SCC morphology. Secondary analysis of published human sinus single-cell RNAseq data did not uncover TAS2R or canonical taste transduction transcripts in multiciliated cells. These findings indicate that the sinus has higher expression of SCC markers than the nasal cavity in chronic rhinosinusitis patients, comprising a rare cell type. Biopsies obtained from the ethmoid sinus may serve as the best location for study of human upper airway taste receptors and SCCs.
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Affiliation(s)
- Jingguo Chen
- Department of Otolaryngology-Head and Neck Surgery, The Second Affiliated Hospital, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | - Eric D Larson
- Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | - Catherine B Anderson
- Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | | | - Daniel N Frank
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Sue C Kinnamon
- Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | - Vijay R Ramakrishnan
- Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, Aurora, CO, USA
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16
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Abstract
Forkhead box protein J1 (FOXJ1), a member of the forkhead family transcription factors, is a transcriptional regulator of motile ciliogenesis. The nasal respiratory epithelium, but not olfactory epithelium, is lined with FOXJ1-expressing multiciliated epithelial cells with motile cilia. In a transgenic mouse where an enhanced green fluorescent protein (eGFP) transgene is driven by the human FOXJ1 promoter, robust eGFP expression is observed not only in the multiciliated cells of the respiratory epithelium but in a distinctive small subset of olfactory sensory neurons in the olfactory epithelium. These eGFP-positive cells lie at the extreme apical part of the neuronal layer and are most numerous in dorsal-medial regions of olfactory epithelium. Interestingly, we observed a corresponding small number of glomeruli in the olfactory bulb wherein eGFP-labeled axons terminate, suggesting that the population of eGFP+ receptor cells expresses a limited number of olfactory receptors. Similarly, a subset of vomeronasal sensory neurons expresses eGFP and is distributed throughout the full height of the vomeronasal sensory epithelium. In keeping with this broad distribution of labeled vomeronasal receptor cells, eGFP-labeled axons terminate in many glomeruli in both anterior and posterior portions of the accessory olfactory bulb. These findings suggest that Foxj1-driven eGFP marks a specific population of olfactory and vomeronasal sensory neurons, although neither receptor cell population possess motile cilia.
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Affiliation(s)
- Eric D Larson
- Department of Otolaryngology, University of Colorado School of Medicine, MS, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, MS, Aurora, CO, USA
| | - Shivani Pathak
- Department of Otolaryngology, University of Colorado School of Medicine, MS, Aurora, CO, USA
| | - Vijay R Ramakrishnan
- Department of Otolaryngology, University of Colorado School of Medicine, MS, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, MS, Aurora, CO, USA
| | - Thomas E Finger
- Department of Otolaryngology, University of Colorado School of Medicine, MS, Aurora, CO, USA.,Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, MS, Aurora, CO, USA.,Department of Cell and Developmental Biology, University of Colorado School of Medicine, MS, Aurora, CO, USA
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17
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Cooper KW, Brann DH, Farruggia MC, Bhutani S, Pellegrino R, Tsukahara T, Weinreb C, Joseph PV, Larson ED, Parma V, Albers MW, Barlow LA, Datta SR, Di Pizio A. COVID-19 and the Chemical Senses: Supporting Players Take Center Stage. Neuron 2020; 107:219-233. [PMID: 32640192 PMCID: PMC7328585 DOI: 10.1016/j.neuron.2020.06.032] [Citation(s) in RCA: 212] [Impact Index Per Article: 53.0] [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: 05/22/2020] [Revised: 06/24/2020] [Accepted: 06/25/2020] [Indexed: 12/11/2022]
Abstract
The main neurological manifestation of COVID-19 is loss of smell or taste. The high incidence of smell loss without significant rhinorrhea or nasal congestion suggests that SARS-CoV-2 targets the chemical senses through mechanisms distinct from those used by endemic coronaviruses or other common cold-causing agents. Here we review recently developed hypotheses about how SARS-CoV-2 might alter the cells and circuits involved in chemosensory processing and thereby change perception. Given our limited understanding of SARS-CoV-2 pathogenesis, we propose future experiments to elucidate disease mechanisms and highlight the relevance of this ongoing work to understanding how the virus might alter brain function more broadly.
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Affiliation(s)
- Keiland W Cooper
- Interdepartmental Neuroscience Program, University of California Irvine, Irvine, CA, USA
| | - David H Brann
- Harvard Medical School Department of Neurobiology, Boston, MA, USA
| | | | - Surabhi Bhutani
- School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA, USA
| | - Robert Pellegrino
- Department of Food Science, Institute of Agriculture, University of Tennessee, Knoxville, TN, USA; Smell & Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden, Germany
| | | | - Caleb Weinreb
- Harvard Medical School Department of Neurobiology, Boston, MA, USA
| | - Paule V Joseph
- Division of Intramural Research, National Institute of Nursing Research (NINR) National Institutes of Health, Bethesda, MD, USA; National Institute on Alcohol Abuse and Alcoholism (NIAAA) National Institutes of Health, Bethesda, MD, USA
| | - Eric D Larson
- Department of Otolaryngology, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA and the Rocky Mountain Taste and Smell Center, Aurora, CO, USA
| | - Valentina Parma
- Department of Psychology, Temple University, Philadelphia, PA, USA
| | - Mark W Albers
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Linda A Barlow
- Department of Cell and Developmental Biology, Graduate Program in Cell Biology, Stem Cells and Development and the Rocky Mountain Taste and Smell Center, University of Colorado, School Medicine, Anschutz Medical Campus, Aurora, CO, USA.
| | | | - Antonella Di Pizio
- Leibniz Institute for Food Systems Biology at the Technical University of Munich, Freising, Germany.
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18
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Baschal EE, Larson ED, Bootpetch Roberts TC, Pathak S, Frank G, Handley E, Dinwiddie J, Moloney M, Yoon PJ, Gubbels SP, Scholes MA, Cass SP, Jenkins HA, Frank DN, Yang IV, Schwartz DA, Ramakrishnan VR, Santos-Cortez RLP. Identification of Novel Genes and Biological Pathways That Overlap in Infectious and Nonallergic Diseases of the Upper and Lower Airways Using Network Analyses. Front Genet 2020; 10:1352. [PMID: 32010199 PMCID: PMC6979043 DOI: 10.3389/fgene.2019.01352] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 12/10/2019] [Indexed: 12/16/2022] Open
Abstract
Previous genetic studies on susceptibility to otitis media and airway infections have focused on immune pathways acting within the local mucosal epithelium, and outside of allergic rhinitis and asthma, limited studies exist on the overlaps at the gene, pathway or network level between the upper and lower airways. In this report, we compared [1] pathways identified from network analysis using genes derived from published genome-wide family-based and association studies for otitis media, sinusitis, and lung phenotypes, to [2] pathways identified using differentially expressed genes from RNA-sequence data from lower airway, sinus, and middle ear tissues, in particular cholesteatoma tissue compared to middle ear mucosa. For otitis media, a large number of genes (n = 1,806) were identified as differentially expressed between cholesteatoma and middle ear mucosa, which in turn led to the identification of 68 pathways that are enriched in cholesteatoma. Two differentially expressed genes CR1 and SAA1 overlap in middle ear, sinus, and lower airway samples and are potentially novel genes for otitis media susceptibility. In addition, 56 genes were differentially expressed in both tissues from the middle ear and either sinus or lower airways. Pathways that are common in upper and lower airway diseases, whether from published DNA studies or from our RNA-sequencing analyses, include chromatin organization/remodeling, endocytosis, immune system process, protein folding, and viral process. Taken together, our findings from genetic susceptibility and differential tissue expression studies support the hypothesis that the unified airway theory wherein the upper and lower respiratory tracts act as an integrated unit also applies to infectious and nonallergic airway epithelial disease. Our results may be used as reference for identification of genes or pathways that are relevant to upper and lower airways, whether common across sites, or unique to each disease.
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Affiliation(s)
- Erin E Baschal
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Eric D Larson
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Tori C Bootpetch Roberts
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Shivani Pathak
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Gretchen Frank
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Elyse Handley
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, CO, United States
| | - Jordyn Dinwiddie
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, CO, United States
| | - Molly Moloney
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Patricia J Yoon
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, CO, United States
| | - Samuel P Gubbels
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Melissa A Scholes
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, CO, United States
| | - Stephen P Cass
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Herman A Jenkins
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Daniel N Frank
- Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Ivana V Yang
- Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - David A Schwartz
- Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Vijay R Ramakrishnan
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Regie Lyn P Santos-Cortez
- Department of Otolaryngology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
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19
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Larson ED, Magno JPM, Steritz MJ, Llanes EGDV, Cardwell J, Pedro M, Roberts TB, Einarsdottir E, Rosanes RAQ, Greenlee C, Santos RAP, Yousaf A, Streubel SO, Santos ATR, Ruiz AG, Lagrana-Villagracia SM, Ray D, Yarza TKL, Scholes MA, Anderson CB, Acharya A, Gubbels SP, Bamshad MJ, Cass SP, Lee NR, Shaikh RS, Nickerson DA, Mohlke KL, Prager JD, Cruz TLG, Yoon PJ, Abes GT, Schwartz DA, Chan AL, Wine TM, Cutiongco-de la Paz EM, Friedman N, Kechris K, Kere J, Leal SM, Yang IV, Patel JA, Tantoco MLC, Riazuddin S, Chan KH, Mattila PS, Reyes-Quintos MRT, Ahmed ZM, Jenkins HA, Chonmaitree T, Hafrén L, Chiong CM, Santos-Cortez RLP. A2ML1 and otitis media: novel variants, differential expression, and relevant pathways. Hum Mutat 2019; 40:1156-1171. [PMID: 31009165 DOI: 10.1002/humu.23769] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [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: 10/30/2018] [Revised: 02/26/2019] [Accepted: 04/18/2019] [Indexed: 12/16/2022]
Abstract
A genetic basis for otitis media is established, however, the role of rare variants in disease etiology is largely unknown. Previously a duplication variant within A2ML1 was identified as a significant risk factor for otitis media in an indigenous Filipino population and in US children. In this report exome and Sanger sequencing was performed using DNA samples from the indigenous Filipino population, Filipino cochlear implantees, US probands, Finnish, and Pakistani families with otitis media. Sixteen novel, damaging A2ML1 variants identified in otitis media patients were rare or low-frequency in population-matched controls. In the indigenous population, both gingivitis and A2ML1 variants including the known duplication variant and the novel splice variant c.4061 + 1 G>C were independently associated with otitis media. Sequencing of salivary RNA samples from indigenous Filipinos demonstrated lower A2ML1 expression according to the carriage of A2ML1 variants. Sequencing of additional salivary RNA samples from US patients with otitis media revealed differentially expressed genes that are highly correlated with A2ML1 expression levels. In particular, RND3 is upregulated in both A2ML1 variant carriers and high-A2ML1 expressors. These findings support a role for A2ML1 in keratinocyte differentiation within the middle ear as part of otitis media pathology and the potential application of ROCK inhibition in otitis media.
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Affiliation(s)
- Eric D Larson
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Jose Pedrito M Magno
- Department of Otorhinolaryngology, University of the Philippines Manila College of Medicine - Philippine General Hospital, Manila, Philippines
| | - Matthew J Steritz
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Erasmo Gonzalo D V Llanes
- Department of Otorhinolaryngology, University of the Philippines Manila College of Medicine - Philippine General Hospital, Manila, Philippines.,Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines
| | - Jonathan Cardwell
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado
| | - Melquiadesa Pedro
- Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines
| | - Tori Bootpetch Roberts
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Elisabet Einarsdottir
- Folkhälsan Institute of Genetics and Molecular Neurology Research Program, University of Helsinki, Helsinki, Finland.,Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Rose Anne Q Rosanes
- Department of Community Dentistry, College of Dentistry, University of the Philippines Manila, Manila, Philippines
| | - Christopher Greenlee
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, Colorado
| | | | - Ayesha Yousaf
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Punjab, Pakistan
| | - Sven-Olrik Streubel
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, Colorado
| | | | - Amanda G Ruiz
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, Colorado
| | - Sheryl Mae Lagrana-Villagracia
- Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines
| | - Dylan Ray
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Talitha Karisse L Yarza
- Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines.,Newborn Hearing Screening Reference Center, University of the Philippines Manila - National Institutes of Health (NIH), Manila, Philippines
| | - Melissa A Scholes
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, Colorado
| | - Catherine B Anderson
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Anushree Acharya
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | | | - Samuel P Gubbels
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Michael J Bamshad
- Department of Genome Sciences, University of Washington, Seattle, Washington
| | - Stephen P Cass
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Nanette R Lee
- USC-Office of Population Studies Foundation, Inc. and Department of Anthropology, Sociology and History, University of San Carlos, Cebu, Philippines
| | - Rehan S Shaikh
- Institute of Molecular Biology and Biotechnology, Bahauddin Zakariya University, Multan, Punjab, Pakistan
| | - Deborah A Nickerson
- Department of Genome Sciences, University of Washington, Seattle, Washington
| | - Karen L Mohlke
- Department of Genetics, University of North Carolina, Chapel Hill, North Carolina
| | - Jeremy D Prager
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, Colorado
| | - Teresa Luisa G Cruz
- Department of Otorhinolaryngology, University of the Philippines Manila College of Medicine - Philippine General Hospital, Manila, Philippines.,Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines
| | - Patricia J Yoon
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, Colorado
| | - Generoso T Abes
- Department of Otorhinolaryngology, University of the Philippines Manila College of Medicine - Philippine General Hospital, Manila, Philippines.,Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines
| | - David A Schwartz
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado
| | - Abner L Chan
- Department of Otorhinolaryngology, University of the Philippines Manila College of Medicine - Philippine General Hospital, Manila, Philippines.,Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines
| | - Todd M Wine
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, Colorado
| | - Eva Maria Cutiongco-de la Paz
- Philippine Genome Center, University of the Philippines, Quezon City, Philippines.,University of the Philippines Manila - National Institutes of Health, Manila, Philippines
| | - Norman Friedman
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, Colorado
| | - Katerina Kechris
- Department of Biostatistics and Bioinformatics, Colorado School of Public Health, Aurora, Colorado
| | - Juha Kere
- Folkhälsan Institute of Genetics and Molecular Neurology Research Program, University of Helsinki, Helsinki, Finland.,Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden
| | - Suzanne M Leal
- Center for Statistical Genetics, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Ivana V Yang
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado
| | - Janak A Patel
- Division of Infectious Diseases, Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas
| | - Ma Leah C Tantoco
- Department of Otorhinolaryngology, University of the Philippines Manila College of Medicine - Philippine General Hospital, Manila, Philippines.,Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines
| | - Saima Riazuddin
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Kenny H Chan
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado.,Department of Pediatric Otolaryngology, Children's Hospital Colorado, Aurora, Colorado
| | - Petri S Mattila
- Department of Otorhinolaryngology, Head & Neck Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Maria Rina T Reyes-Quintos
- Department of Otorhinolaryngology, University of the Philippines Manila College of Medicine - Philippine General Hospital, Manila, Philippines.,Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines.,Newborn Hearing Screening Reference Center, University of the Philippines Manila - National Institutes of Health (NIH), Manila, Philippines.,University of the Philippines Manila - National Institutes of Health, Manila, Philippines
| | - Zubair M Ahmed
- Department of Otorhinolaryngology, Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, Maryland
| | - Herman A Jenkins
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Tasnee Chonmaitree
- Division of Infectious Diseases, Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas
| | - Lena Hafrén
- Department of Otorhinolaryngology, Head & Neck Surgery, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Charlotte M Chiong
- Department of Otorhinolaryngology, University of the Philippines Manila College of Medicine - Philippine General Hospital, Manila, Philippines.,Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines.,Newborn Hearing Screening Reference Center, University of the Philippines Manila - National Institutes of Health (NIH), Manila, Philippines
| | - Regie Lyn P Santos-Cortez
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado.,Philippine National Ear Institute, University of the Philippines Manila - National Institutes of Health, Manila, Philippines.,Center for Children's Surgery, Children's Hospital Colorado, Aurora, Colorado
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20
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Green CA, Goodsitt MM, Brock KK, Davis CL, Larson ED, Lau JH, Carson PL. Deformable mapping technique to correlate lesions in digital breast tomosynthesis and automated breast ultrasound images. Med Phys 2018; 45:4402-4417. [PMID: 30066340 DOI: 10.1002/mp.13113] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [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: 12/21/2017] [Revised: 07/22/2018] [Accepted: 07/26/2018] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To develop a deformable mapping technique to match corresponding lesions between digital breast tomosynthesis (DBT) and automated breast ultrasound (ABUS) images. METHODS External fiducial markers were attached to the surface of two CIRS multi-modality compressible breast phantoms (A and B) containing multiple simulated lesions. Both phantoms were imaged with DBT (upright positioning with cranial-caudal compression) and ABUS (supine positioning with anterior-to-chest wall compression). The lesions and markers were manually segmented by three different readers. Reader segmentation similarity and reader reproducibility were assessed using Dice similarity coefficients (DSC) and distances between centers of mass (dCOM ). For deformable mapping between the modalities each reader's segmented dataset was processed with an automated deformable mapping algorithm as follows: First, Morfeus, a finite element (FE) based multi-organ deformable image registration platform, converted segmentations into triangular surface meshes. Second, Altair HyperMesh, a FE pre-processor, created base FE models for the ABUS and DBT data sets. All deformation is performed on the DBT image data; the ABUS image sets remain fixed throughout the process. Deformation was performed on the external skin contour (DBT image set) to match the external skin contour on the ABUS set, and the locations of the external markers were used to morph the skin contours to be within a user-defined distance. Third, the base DBT-FE model was deformed with the FE analysis solver, Optistruct. Deformed DBT lesions were correlated with matching lesions in the base ABUS FE model. Performance (lesion correlation) was assessed with dCOM for all corresponding lesions and lesion overlap. Analysis was performed to determine the minimum number of external fiducial markers needed to create the desired correlation and the improvement of correlation with the use of external markers. RESULTS Average DSC for reader similarity ranged from 0.88 to 0.91 (ABUS) and 0.57 to 0.83 (DBT). Corresponding dCOM ranged from 0.20 to 0.36 mm (ABUS) and 0.11 to 1.16 mm (DBT). Lesion correlation is maximized when all corresponding markers are within a maximum distance of 5 mm. For deformable mapping of phantom A, without the use of external markers, only two of six correlated lesions showed overlap with an average lesion dCOM of 6.8 ± 2.8 mm. With use of three external fiducial markers, five of six lesions overlapped and average dCOM improved to 4.9 ± 2.4 mm. For deformable mapping of Phantom B without external markers analysis, four lesions were correlated of seven with overlap between only one of seven lesions, and an average lesion dCOM of 9.7 ± 3.5 mm. With three external markers, all seven possible lesions were correlated with overlap between four of seven lesions. The average dCOM was 8.5 ± 4.0 mm. CONCLUSION This work demonstrates the potential for a deformable mapping technique to relate corresponding lesions in DBT and ABUS images by showing improved lesion correspondence and reduced lesion registration errors with the use of external fiducial markers. The technique should improve radiologists' characterization of breast lesions which can reduce patient callbacks, misdiagnoses and unnecessary biopsies.
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Affiliation(s)
- Crystal A Green
- Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI, 48109, USA.,Department of Radiology, University of Michigan Health System, Ann Arbor, MI, 48109, USA
| | - Mitchell M Goodsitt
- Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI, 48109, USA.,Department of Radiology, University of Michigan Health System, Ann Arbor, MI, 48109, USA
| | - Kristy K Brock
- Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI, 48109, USA.,Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | | | - Eric D Larson
- Department of Radiology, University of Michigan Health System, Ann Arbor, MI, 48109, USA
| | - Jasmine H Lau
- Department of Radiology, University of Michigan Health System, Ann Arbor, MI, 48109, USA
| | - Paul L Carson
- Department of Radiology, University of Michigan Health System, Ann Arbor, MI, 48109, USA
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21
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Larson ED, Lee WM, Roubidoux MA, Goodsitt MM, Lashbrook C, Davis CE, Kripfgans OD, Carson PL. Preliminary Clinical Experience with a Combined Automated Breast Ultrasound and Digital Breast Tomosynthesis System. Ultrasound Med Biol 2018; 44:734-742. [PMID: 29311005 PMCID: PMC5801205 DOI: 10.1016/j.ultrasmedbio.2017.12.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Revised: 11/29/2017] [Accepted: 12/03/2017] [Indexed: 06/02/2023]
Abstract
We analyzed the performance of a mammographically configured, automated breast ultrasound (McABUS) scanner combined with a digital breast tomosynthesis (DBT) system. The GE Invenia ultrasound system was modified for integration with GE DBT systems. Ultrasound and DBT imaging were performed in the same mammographic compression. Our small preliminary study included 13 cases, six of whom had contained invasive cancers. From analysis of these cases, current limitations and corresponding potential improvements of the system were determined. A registration analysis was performed to compare the ease of McABUS to DBT registration for this system with that of two systems designed previously. It was observed that in comparison to data from an earlier study, the McABUS-to-DBT registration alignment errors for both this system and a previously built combined system were smaller than those for a previously built standalone McABUS system.
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Affiliation(s)
- Eric D Larson
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA.
| | - Won-Mean Lee
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | | | | | - Chris Lashbrook
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Oliver D Kripfgans
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Paul L Carson
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
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22
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Ramakrishnan VR, Gonzalez JR, Cooper SE, Barham HP, Anderson CB, Larson ED, Cool CD, Diller JD, Jones K, Kinnamon SC. RNA sequencing and pathway analysis identify tumor necrosis factor alpha driven small proline-rich protein dysregulation in chronic rhinosinusitis. Am J Rhinol Allergy 2017; 31:283-288. [PMID: 28859701 PMCID: PMC5590176 DOI: 10.2500/ajra.2017.31.4457] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [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] [Indexed: 12/13/2022]
Abstract
BACKGROUND Chronic rhinosinusitis (CRS) is a heterogeneous inflammatory disorder in which many pathways contribute to end-organ disease. Small proline-rich proteins (SPRR) are polypeptides that have recently been shown to contribute to epithelial biomechanical properties relevant in T-helper type 2 inflammation. There is evidence that genetic polymorphism in SPRR genes may predict the development of asthma in children with atopy and, correlatively, that expression of SPRRs is increased under allergic conditions, which leads to epithelial barrier dysfunction in atopic disease. METHODS RNAs from uncinate tissue specimens from patients with CRS and control subjects were compared by RNA sequencing by using Ingenuity Pathway Analysis (n = 4 each), and quantitative polymerase chain reaction (PCR) (n = 15). A separate cohort of archived sinus tissue was examined by immunohistochemistry (n = 19). RESULTS A statistically significant increase of SPRR expression in CRS sinus tissue was identified that was not a result of atopic presence. SPRR1 and SPRR2A expressions were markedly increased in patients with CRS (p < 0.01) on RNA sequencing, with confirmation by using real-time PCR. Immunohistochemistry of archived surgical samples demonstrated staining of SPRR proteins within squamous epithelium of both groups. Pathway analysis indicated tumor necrosis factor (TNF) alpha as a master regulator of the SPRR gene products. CONCLUSION Expression of SPRR1 and of SPRR2A is increased in mucosal samples from patients with CRS and appeared as a downstream result of TNF alpha modulation, which possibly resulted in epithelial barrier dysfunction.
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Affiliation(s)
- Vijay R. Ramakrishnan
- From the Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Joseph R. Gonzalez
- From the Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Sarah E. Cooper
- From the Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Henry P. Barham
- From the Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - Catherine B. Anderson
- Rocky Mountain Taste and Smell Center, Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado
| | - Eric D. Larson
- Rocky Mountain Taste and Smell Center, Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado
| | - Carlyne D. Cool
- Department of Pathology, University of Colorado School of Medicine, Aurora, Colorado, and
| | - John D. Diller
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, Colorado
| | - Kenneth Jones
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, Colorado
| | - Sue C. Kinnamon
- From the Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
- Rocky Mountain Taste and Smell Center, Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado
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23
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Bhattarai Y, Schmidt BA, Linden DR, Larson ED, Grover M, Beyder A, Farrugia G, Kashyap PC. Human-derived gut microbiota modulates colonic secretion in mice by regulating 5-HT 3 receptor expression via acetate production. Am J Physiol Gastrointest Liver Physiol 2017; 313:G80-G87. [PMID: 28408644 PMCID: PMC5538830 DOI: 10.1152/ajpgi.00448.2016] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 03/28/2017] [Accepted: 04/05/2017] [Indexed: 01/31/2023]
Abstract
Serotonin [5-hydroxytryptamine (5-HT)], an important neurotransmitter and a paracrine messenger in the gastrointestinal tract, regulates intestinal secretion by its action primarily on 5-HT3 and 5-HT4 receptors. Recent studies highlight the role of gut microbiota in 5-HT biosynthesis. In this study, we determine whether human-derived gut microbiota affects host secretory response to 5-HT and 5-HT receptor expression. We used proximal colonic mucosa-submucosa preparation from age-matched Swiss Webster germ-free (GF) and humanized (HM; ex-GF colonized with human gut microbiota) mice. 5-HT evoked a significantly greater increase in short-circuit current (ΔIsc) in GF compared with HM mice. Additionally, 5-HT3 receptor mRNA and protein expression was significantly higher in GF compared with HM mice. Ondansetron, a 5-HT3 receptor antagonist, inhibited 5-HT-evoked ΔIsc in GF mice but not in HM mice. Furthermore, a 5-HT3 receptor-selective agonist, 2-methyl-5-hydroxytryptamine hydrochloride, evoked a significantly higher ΔIsc in GF compared with HM mice. Immunohistochemistry in 5-HT3A-green fluorescent protein mice localized 5-HT3 receptor expression to enterochromaffin cells in addition to nerve fibers. The significant difference in 5-HT-evoked ΔIsc between GF and HM mice persisted in the presence of tetrodotoxin (TTX) but was lost after ondansetron application in the presence of TTX. Application of acetate (10 mM) significantly lowered 5-HT3 receptor mRNA in GF mouse colonoids. We conclude that host secretory response to 5-HT may be modulated by gut microbiota regulation of 5-HT3 receptor expression via acetate production. Epithelial 5-HT3 receptor may function as a mediator of gut microbiota-driven change in intestinal secretion.NEW & NOTEWORTHY We found that gut microbiota alters serotonin (5-HT)-evoked intestinal secretion in a 5-HT3 receptor-dependent mechanism and gut microbiota metabolite acetate alters 5-HT3 receptor expression in colonoids.View this article's corresponding video summary at https://www.youtube.com/watch?v=aOMYJMuLTcw&feature=youtu.be.
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Affiliation(s)
- Yogesh Bhattarai
- 1Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota;
| | - Bradley A. Schmidt
- 3Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - David R. Linden
- 3Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Eric D. Larson
- 2Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado; and
| | - Madhusudan Grover
- 1Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota;
| | - Arthur Beyder
- 1Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota;
| | - Gianrico Farrugia
- 1Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota;
| | - Purna C. Kashyap
- 1Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota;
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24
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Stratford JM, Larson ED, Yang R, Salcedo E, Finger TE. 5-HT 3A -driven green fluorescent protein delineates gustatory fibers innervating sour-responsive taste cells: A labeled line for sour taste? J Comp Neurol 2017; 525:2358-2375. [PMID: 28316078 DOI: 10.1002/cne.24209] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [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: 01/16/2017] [Revised: 03/03/2017] [Accepted: 03/10/2017] [Indexed: 12/29/2022]
Abstract
Taste buds contain multiple cell types with each type expressing receptors and transduction components for a subset of taste qualities. The sour sensing cells, Type III cells, release serotonin (5-HT) in response to the presence of sour (acidic) tastants and this released 5-HT activates 5-HT3 receptors on the gustatory nerves. We show here, using 5-HT3A GFP mice, that 5-HT3 -expressing nerve fibers preferentially contact and receive synaptic contact from Type III taste cells. Further, these 5-HT3 -expressing nerve fibers terminate in a restricted central-lateral portion of the nucleus of the solitary tract (nTS)-the same area that shows increased c-Fos expression upon presentation of a sour tastant (30 mM citric acid). This acid stimulation also evokes c-Fos in the laterally adjacent mediodorsal spinal trigeminal nucleus (DMSp5), but this trigeminal activation is not associated with the presence of 5-HT3 -expressing nerve fibers as it is in the nTS. Rather, the neuronal activation in the trigeminal complex likely is attributable to direct depolarization of acid-sensitive trigeminal nerve fibers, for example, polymodal nociceptors, rather than through taste buds. Taken together, these findings suggest that transmission of sour taste information involves communication between Type III taste cells and 5-HT3 -expressing afferent nerve fibers that project to a restricted portion of the nTS consistent with a crude mapping of taste quality information in the primary gustatory nucleus.
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Affiliation(s)
- J M Stratford
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado.,Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, Colorado
| | - E D Larson
- Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, Colorado.,Department of Otolaryngology, University of Colorado School of Medicine, Aurora, Colorado
| | - R Yang
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado.,Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, Colorado
| | - E Salcedo
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado.,Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, Colorado
| | - T E Finger
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado.,Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, Colorado
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25
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Sharpe EJ, Larson ED, Proenza C. Cyclic AMP reverses the effects of aging on pacemaker activity and If in sinoatrial node myocytes. J Gen Physiol 2017; 149:237-247. [PMID: 28057842 PMCID: PMC5299620 DOI: 10.1085/jgp.201611674] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 11/09/2016] [Accepted: 11/22/2016] [Indexed: 12/19/2022] Open
Abstract
Aging reduces pacemaker activity and shifts the voltage dependence of activation of the funny current, If, in sinoatrial node myocytes. Sharpe et al. find that these effects of aging can be reversed by application of exogenous cAMP but not by stimulation of endogenous cAMP. Aerobic capacity decreases with age, in part because of an age-dependent decline in maximum heart rate (mHR) and a reduction in the intrinsic pacemaker activity of the sinoatrial node of the heart. Isolated sinoatrial node myocytes (SAMs) from aged mice have slower spontaneous action potential (AP) firing rates and a hyperpolarizing shift in the voltage dependence of activation of the “funny current,” If. Cyclic AMP (cAMP) is a critical modulator of both AP firing rate and If in SAMs. Here, we test the ability of endogenous and exogenous cAMP to overcome age-dependent changes in acutely isolated murine SAMs. We found that maximal stimulation of endogenous cAMP with 3-isobutyl-1-methylxanthine (IBMX) and forskolin significantly increased AP firing rate and depolarized the voltage dependence of activation of If in SAMs from both young and aged mice. However, these changes were insufficient to overcome the deficits in aged SAMs, and significant age-dependent differences in AP firing rate and If persisted in the presence of IBMX and forskolin. In contrast, the effects of aging on SAMs were completely abolished by a high concentration of exogenous cAMP, which restored AP firing rate and If activation to youthful levels in cells from aged animals. Interestingly, the age-dependent differences in AP firing rates and If were similar in whole-cell and perforated-patch recordings, and the hyperpolarizing shift in If persisted in excised inside-out patches, suggesting a limited role for cAMP in causing these changes. Collectively, the data indicate that aging does not impose an absolute limit on pacemaker activity and that it does not act by simply reducing the concentration of freely diffusible cAMP in SAMs.
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Affiliation(s)
- Emily J Sharpe
- Department of Physiology and Biophysics, University of Colorado-Anschutz Medical Campus, Aurora, CO 80045
| | - Eric D Larson
- Department of Physiology and Biophysics, University of Colorado-Anschutz Medical Campus, Aurora, CO 80045
| | - Catherine Proenza
- Department of Physiology and Biophysics, University of Colorado-Anschutz Medical Campus, Aurora, CO 80045 .,Department of Medicine, Division of Cardiology, University of Colorado-Anschutz Medical Campus, Aurora, CO 80045
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Larson ED, Lee WM, Roubidoux MA, Goodsitt MM, Lashbrook C, Zafar F, Kripfgans OD, Thomenius K, Carson PL. Automated Breast Ultrasound: Dual-Sided Compared with Single-Sided Imaging. Ultrasound Med Biol 2016; 42:2072-2082. [PMID: 27264914 PMCID: PMC5047064 DOI: 10.1016/j.ultrasmedbio.2016.05.001] [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] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 03/08/2016] [Accepted: 05/02/2016] [Indexed: 06/02/2023]
Abstract
The design and performance of a mammographically configured, dual-sided, automated breast ultrasound (ABUS) 3-D imaging system are described. Dual-sided imaging (superior and inferior) is compared with single-sided imaging to aid decisions on clinical implementation of the more complex, but potentially higher-quality dual-sided imaging. Marked improvement in image quality and coverage of the breast is obtained in dual-sided ultrasound over single-sided ultrasound. Among hypo-echoic masses imaged, there are increases in the mean contrast-to-noise ratio of 57% and 79%, respectively, for spliced dual-sided versus superior or inferior single-sided imaging. The fractional breast volume coverage, defined as the percentage volume in the transducer field of view that is imaged with clinically acceptable quality, is improved from 59% in both superior and inferior single-sided imaging to 89% in dual-sided imaging. Applying acoustic coupling to the breast requires more effort or sophisticated methods in dual-sided imaging than in single-sided imaging.
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Affiliation(s)
- Eric D Larson
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Won-Mean Lee
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Mitchel M Goodsitt
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Chris Lashbrook
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Fouzaan Zafar
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Oliver D Kripfgans
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Paul L Carson
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA.
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McCloy DR, Larson ED, Lau B, Lee AKC. Temporal alignment of pupillary response with stimulus events via deconvolution. J Acoust Soc Am 2016; 139:EL57-62. [PMID: 27036288 PMCID: PMC5392052 DOI: 10.1121/1.4943787] [Citation(s) in RCA: 13] [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] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 02/05/2016] [Indexed: 05/27/2023]
Abstract
Analysis of pupil dilation has been used as an index of attentional effort in the auditory domain. Previous work has modeled the pupillary response to attentional effort as a linear time-invariant system with a characteristic impulse response, and used deconvolution to estimate the attentional effort that gives rise to changes in pupil size. Here it is argued that one parameter of the impulse response (the latency of response maximum, t(max)) has been mis-estimated in the literature; a different estimate is presented, and it is shown how deconvolution with this value of t(max) yields more intuitively plausible and informative results.
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Affiliation(s)
- Daniel R McCloy
- Institute for Learning and Brain Sciences, University of Washington, 1715 NE Columbia Road, Box 357988, Seattle, Washington, 98195-7988, USA , , ,
| | - Eric D Larson
- Institute for Learning and Brain Sciences, University of Washington, 1715 NE Columbia Road, Box 357988, Seattle, Washington, 98195-7988, USA , , ,
| | - Bonnie Lau
- Institute for Learning and Brain Sciences, University of Washington, 1715 NE Columbia Road, Box 357988, Seattle, Washington, 98195-7988, USA , , ,
| | - Adrian K C Lee
- Institute for Learning and Brain Sciences, University of Washington, 1715 NE Columbia Road, Box 357988, Seattle, Washington, 98195-7988, USA , , ,
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Vandenbeuch A, Larson ED, Anderson CB, Smith SA, Ford AP, Finger TE, Kinnamon SC. Postsynaptic P2X3-containing receptors in gustatory nerve fibres mediate responses to all taste qualities in mice. J Physiol 2015; 593:1113-25. [PMID: 25524179 DOI: 10.1113/jphysiol.2014.281014] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 12/12/2014] [Indexed: 12/15/2022] Open
Abstract
Taste buds release ATP to activate ionotropic purinoceptors composed of P2X2 and P2X3 subunits, present on the taste nerves. Mice with genetic deletion of P2X2 and P2X3 receptors (double knockout mice) lack responses to all taste stimuli presumably due to the absence of ATP-gated receptors on the afferent nerves. Recent experiments on the double knockout mice showed, however, that their taste buds fail to release ATP, suggesting the possibility of pleiotropic deficits in these global knockouts. To test further the role of postsynaptic P2X receptors in afferent signalling, we used AF-353, a selective antagonist of P2X3-containing receptors to inhibit the receptors acutely during taste nerve recording and behaviour. The specificity of AF-353 for P2X3-containing receptors was tested by recording Ca(2+) transients to exogenously applied ATP in fura-2 loaded isolated geniculate ganglion neurons from wild-type and P2X3 knockout mice. ATP responses were completely inhibited by 10 μm or 100 μm AF-353, but neither concentration blocked responses in P2X3 single knockout mice wherein the ganglion cells express only P2X2-containing receptors. Furthermore, AF-353 had no effect on taste-evoked ATP release from taste buds. In wild-type mice, i.p. injection of AF-353 or simple application of the drug directly to the tongue, inhibited taste nerve responses to all taste qualities in a dose-dependent fashion. A brief access behavioural assay confirmed the electrophysiological results and showed that preference for a synthetic sweetener, SC-45647, was abolished following i.p. injection of AF-353. These data indicate that activation of P2X3-containing receptors is required for transmission of all taste qualities.
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Affiliation(s)
- Aurelie Vandenbeuch
- Department of Otolaryngology, University of Colorado School of Medicine, Aurora, CO, USA; Rocky Mountain Taste and Smell Center, University of Colorado School of Medicine, Aurora, CO, USA
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Mohammadi M, Larson ED, Liu J, Larson RG. Brownian dynamics simulations of coagulation of dilute uniform and anisotropic particles under shear flow spanning low to high Peclet numbers. J Chem Phys 2015; 142:024108. [DOI: 10.1063/1.4905098] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Maziar Mohammadi
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Eric D. Larson
- Engineering Physics Program, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Jun Liu
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Ronald G. Larson
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
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Sharpe EJ, Larson ED, Proenza C. Aging Alters cAMP Signaling and Membrane-Delimited Regulation of if in Sinoatrial Myocytes. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.1491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Liu G, Larson ED. Comparison of Coal/Biomass Co-processing Systems with CCS for Production of Low-carbon Synthetic Fuels: Methanol-to-Gasoline and Fischer-tropsch. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.egypro.2014.11.768] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Groenke S, Larson ED, Alber S, Zhang R, Lamp ST, Ren X, Nakano H, Jordan MC, Karagueuzian HS, Roos KP, Nakano A, Proenza C, Philipson KD, Goldhaber JI. Complete atrial-specific knockout of sodium-calcium exchange eliminates sinoatrial node pacemaker activity. PLoS One 2013; 8:e81633. [PMID: 24278453 PMCID: PMC3836769 DOI: 10.1371/journal.pone.0081633] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [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: 08/27/2013] [Accepted: 10/25/2013] [Indexed: 11/18/2022] Open
Abstract
The origin of sinoatrial node (SAN) pacemaker activity in the heart is controversial. The leading candidates are diastolic depolarization by "funny" current (If) through HCN4 channels (the "Membrane Clock" hypothesis), depolarization by cardiac Na-Ca exchange (NCX1) in response to intracellular Ca cycling (the "Calcium Clock" hypothesis), and a combination of the two ("Coupled Clock"). To address this controversy, we used Cre/loxP technology to generate atrial-specific NCX1 KO mice. NCX1 protein was undetectable in KO atrial tissue, including the SAN. Surface ECG and intracardiac electrograms showed no atrial depolarization and a slow junctional escape rhythm in KO that responded appropriately to β-adrenergic and muscarinic stimulation. Although KO atria were quiescent they could be stimulated by external pacing suggesting that electrical coupling between cells remained intact. Despite normal electrophysiological properties of If in isolated patch clamped KO SAN cells, pacemaker activity was absent. Recurring Ca sparks were present in all KO SAN cells, suggesting that Ca cycling persists but is uncoupled from the sarcolemma. We conclude that NCX1 is required for normal pacemaker activity in murine SAN.
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Affiliation(s)
- Sabine Groenke
- Cardiovascular Research Laboratories, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Eric D. Larson
- Department of Physiology & Biophysics, University of Colorado School of Medicine, Denver, Colorado, United States of America
| | - Sarah Alber
- Department of Physiology & Biophysics, University of Colorado School of Medicine, Denver, Colorado, United States of America
| | - Rui Zhang
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California, United States of America
| | - Scott T. Lamp
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California, United States of America
| | - Xiaoyan Ren
- Cardiovascular Research Laboratories, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Haruko Nakano
- Department of Molecular, Cell and Developmental Biology, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California Los Angeles, Los Angeles, California, United States of America
| | - Maria C. Jordan
- Cardiovascular Research Laboratories, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Hrayr S. Karagueuzian
- Cardiovascular Research Laboratories, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Kenneth P. Roos
- Cardiovascular Research Laboratories, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Atsushi Nakano
- Department of Molecular, Cell and Developmental Biology, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California Los Angeles, Los Angeles, California, United States of America
| | - Catherine Proenza
- Department of Physiology & Biophysics, University of Colorado School of Medicine, Denver, Colorado, United States of America
| | - Kenneth D. Philipson
- Cardiovascular Research Laboratories, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Joshua I. Goldhaber
- Heart Institute, Cedars-Sinai Medical Center, Los Angeles, California, United States of America
- * E-mail:
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Abstract
Hyperpolarization-activated, cyclic nucleotide-sensitive (HCN4) channels produce the "funny current," I(f), which contributes to spontaneous pacemaking in sinoatrial myocytes (SAMs). The C-terminus of HCN channels inhibits voltage-dependent gating, and cAMP binding relieves this "autoinhibition." We previously showed 1) that autoinhibition in HCN4 can be relieved in the absence of cAMP in some cellular contexts and 2) that PKA is required for β adrenergic receptor (βAR) signaling to HCN4 in SAMs. Together, these results raise the possibility that native HCN channels in SAMs may be insensitive to direct activation by cAMP. Here, we examined PKA-independent activation of If by cAMP in SAMs. We observed similar robust activation of If by exogenous cAMP and Rp-cAMP (an analog than cannot activate PKA). Thus PKA-dependent βAR-to-HCN signaling does not result from cAMP insensitivity of sinoatrial HCN channels and might instead arise via PKA-dependent limitation of cAMP production and/or cAMP access to HCN channels in SAMs.
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Affiliation(s)
- Joshua R St Clair
- Department of Physiology and Biophysics; University of Colorado Denver-Anschutz Medical Campus; Aurora, CO USA
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Liao Z, Lockhead D, St Clair JR, Larson ED, Wilson CE, Proenza C. Cellular context and multiple channel domains determine cAMP sensitivity of HCN4 channels: ligand-independent relief of autoinhibition in HCN4. ACTA ACUST UNITED AC 2013; 140:557-66. [PMID: 23109717 PMCID: PMC3483121 DOI: 10.1085/jgp.201210858] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Hyperpolarization-activated, cyclic nucleotide–sensitive (HCN) channels produce the If and Ih currents, which are critical for cardiac pacemaking and neuronal excitability, respectively. HCN channels are modulated by cyclic AMP (cAMP), which binds to a conserved cyclic nucleotide–binding domain (CNBD) in the C terminus. The unliganded CNBD has been shown to inhibit voltage-dependent gating of HCNs, and cAMP binding relieves this “autoinhibition,” causing a depolarizing shift in the voltage dependence of activation. Here we report that relief of autoinhibition can occur in the absence of cAMP in a cellular context- and isoform-dependent manner: when the HCN4 isoform was expressed in Chinese hamster ovary (CHO) cells, the basal voltage dependence was already shifted to more depolarized potentials and cAMP had no further effect on channel activation. This “pre-relief” of autoinhibition was specific both to HCN4 and to CHO cells; cAMP shifted the voltage dependence of HCN2 in CHO cells and of HCN4 in human embryonic kidney (HEK) cells. The pre-relief phenotype did not result from different concentrations of soluble intracellular factors in CHO and HEK cells, as it persisted in excised cell-free patches. Likewise, it did not arise from a failure of cAMP to bind to the CNBD of HCN4 in CHOs, as indicated by cAMP-dependent slowing of deactivation. Instead, a unique ∼300–amino acid region of the distal C terminus of HCN4 (residues 719–1012, downstream of the CNBD) was found to be necessary, but not sufficient, for the depolarized basal voltage dependence and cAMP insensitivity of HCN4 in CHO cells. Collectively, these data suggest a model in which multiple HCN4 channel domains conspire with membrane-associated intracellular factors in CHO cells to relieve autoinhibition in HCN4 channels in the absence of cAMP. These findings raise the possibility that such ligand-independent regulation could tune the activity of HCN channels and other CNBD-containing proteins in many physiological systems.
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Affiliation(s)
- Zhandi Liao
- Department of Physiology and Biophysics, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
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Larson ED, Sumner WA, Bannister RA, Proenza C. Reduced Excitability and Ca2+ Current Density in Sinoatrial Myocytes from Aged Mice. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.1182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Liao Z, St Clair J, Larson ED, Proenza C. Direct cAMP Binding and PKA Phosphorylation Share a Common Gating Mechanism in HCN4 Channels. Biophys J 2012. [DOI: 10.1016/j.bpj.2011.11.3673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Affiliation(s)
- Xiangbo Guo
- Princeton Environmental Institute, Princeton University, Guyot Hall, Washington Road, Princeton, New Jersey 08544, United States
- Research Institute of Petroleum Processing, SINOPEC, Beijing, China
| | - Guangjian Liu
- Princeton Environmental Institute, Princeton University, Guyot Hall, Washington Road, Princeton, New Jersey 08544, United States
- School of Energy and Power Engineering, North China Electric Power University, Beijing 102206, China
| | - Eric D. Larson
- Princeton Environmental Institute, Princeton University, Guyot Hall, Washington Road, Princeton, New Jersey 08544, United States
- Climate Central, 1 Palmer Square, Princeton, New Jersey 08542, United States
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Abstract
Systems with CO2 capture and storage (CCS) that coproduce transportation fuels and electricity from coal plus biomass can address simultaneously challenges of climate change from fossil energy and dependence on imported oil. Under a strong carbon policy, such systems can provide competitively clean low-carbon energy from secure domestic feedstocks by exploiting the negative emissions benefit of underground storage of biomass-derived CO2, the low cost of coal, the scale economies of coal energy conversion, the inherently low cost of CO2 capture, the thermodynamic advantages of coproduction, and expected high oil prices. Such systems require much less biomass to make low-carbon fuels than do biofuels processes. The economics are especially attractive when these coproduction systems are deployed as alternatives to CCS for stand-alone fossil fuel power plants. If CCS proves to be viable as a major carbon mitigation option, the main obstacles to deployment of coproduction systems as power generators would be institutional.
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Affiliation(s)
- Robert H. Williams
- Princeton Environmental Institute, Princeton University, Princeton, New Jersey 08544
| | - Guangjian Liu
- Princeton Environmental Institute, Princeton University, Princeton, New Jersey 08544
- School of Energy and Power Engineering, North China Electric Power University, Beijing 102206, China
| | - Thomas G. Kreutz
- Princeton Environmental Institute, Princeton University, Princeton, New Jersey 08544
| | - Eric D. Larson
- Princeton Environmental Institute, Princeton University, Princeton, New Jersey 08544
- Climate Central, Princeton, New Jersey 08542
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Abstract
The funny current, I(f), in sinoatrial myocytes is thought to contribute to the sympathetic fight-or-flight increase in heart rate. I(f) is produced by hyperpolarization-activated cyclic nucleotide sensitive-4 (HCN4) channels, and it is widely believed that sympathetic regulation of I(f) occurs via direct binding of cAMP to HCN4, independent of phosphorylation. However, we have recently shown that Protein Kinase A (PKA) activity is required for sympathetic regulation of I(f) and that PKA can directly phosphorylate HCN4. In the present study, we examined the effects of a myristoylated PKA inhibitory peptide (myr-PKI) on I(f) in mouse sinoatrial myocytes. We found that myr-PKI and another myristoylated peptide potently and specifically potentiated I(f) via a mechanism that did not involve PKA inhibition and that was independent of the peptide sequence, Protein Kinase C, or phosphatidylinositol-4,5-bisphosphate. The off-target activation of I(f) by myristoylated peptides limits their usefulness for studies of pacemaker mechanisms in sinoatrial myocytes.
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Affiliation(s)
- Zhandi Liao
- Department of Physiology and Biophysics, University of Colorado, Aurora, CO, USA
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Liu G, Williams RH, Larson ED, Kreutz TG. Design/economics of low-carbon power generation from natural gas and biomass with synthetic fuels co-production. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.egypro.2011.02.080] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Liao Z, Lockhead D, Larson ED, Proenza C. Phosphorylation and modulation of hyperpolarization-activated HCN4 channels by protein kinase A in the mouse sinoatrial node. ACTA ACUST UNITED AC 2010; 136:247-58. [PMID: 20713547 PMCID: PMC2931151 DOI: 10.1085/jgp.201010488] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The sympathetic nervous system increases heart rate by activating β adrenergic receptors and increasing cAMP levels in myocytes in the sinoatrial node. The molecular basis for this response is not well understood; however, the cardiac funny current (If) is thought to be among the end effectors for cAMP signaling in sinoatrial myocytes. If is produced by hyperpolarization-activated cyclic nucleotide–sensitive (HCN4) channels, which can be potentiated by direct binding of cAMP to a conserved cyclic nucleotide binding domain in the C terminus of the channels. β adrenergic regulation of If in the sinoatrial node is thought to occur via this direct binding mechanism, independent of phosphorylation. Here, we have investigated whether the cAMP-activated protein kinase (PKA) can also regulate sinoatrial HCN4 channels. We found that inhibition of PKA significantly reduced the ability of β adrenergic agonists to shift the voltage dependence of If in isolated sinoatrial myocytes from mice. PKA also shifted the voltage dependence of activation to more positive potentials for heterologously expressed HCN4 channels. In vitro phosphorylation assays and mass spectrometry revealed that PKA can directly phosphorylate at least 13 sites on HCN4, including at least three residues in the N terminus and at least 10 in the C terminus. Functional analysis of truncated and alanine-substituted HCN4 channels identified a PKA regulatory site in the distal C terminus of HCN4, which is required for PKA modulation of If. Collectively, these data show that native and expressed HCN4 channels can be regulated by PKA, and raise the possibility that this mechanism could contribute to sympathetic regulation of heart rate.
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Affiliation(s)
- Zhandi Liao
- Department of Physiology and Biophysics, Division of Cardiology, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
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Williams RH, Larson ED, Liu G, Kreutz TG. Fischer–Tropsch fuels from coal and biomass: Strategic advantages of once-through (“polygeneration”) configurations. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.egypro.2009.02.252] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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46
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Abstract
Expressed immunoglobulin (Ig) genes undergo alterations in sequence and genomic structure in order to optimize antibody function. A single B cell-specific factor, activation-induced deaminase (AID), initiates these changes by deamination of cytosine to uracil. Uracil in DNA is encountered commonly, and conserved pathways are responsible for its faithful repair. However, at the Ig loci of B cells, AID-initiated damage is processed to produce three distinct outcomes: somatic hypermutation, class switch recombination and gene conversion. This review focuses on the role of AID in Ig gene diversification, emphasizing how AID functions within the mechanism of the Ig gene diversification pathway; and highlights open questions for future research, particularly the most provocative current question: what makes a gene a target for AID-initiated mutagenesis?
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Affiliation(s)
- A C Vallur
- Department of Immunology, University of Washington Medical School, Seattle, Washington 98195-7650, USA
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Larson ED, Drummond JT. Human mismatch repair and G*T mismatch binding by hMutSalpha in vitro is inhibited by adriamycin, actinomycin D, and nogalamycin. J Biol Chem 2001; 276:9775-83. [PMID: 11134041 DOI: 10.1074/jbc.m006390200] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Loss of the human DNA mismatch repair pathway confers cross-resistance to structurally unrelated anticancer drugs. Examples include cisplatin, doxorubicin (adriamycin), and specific alkylating agents. We focused on defining the molecular events that link adriamycin to mismatch repair-dependent drug resistance because adriamycin, unlike drugs that covalently modify DNA, can interact reversibly with DNA. We found that adriamycin, nogalamycin, and actinomycin D comprise a class of drugs that reversibly inhibits human mismatch repair in vitro at low micromolar concentrations. The substrate DNA was not covalently modified by adriamycin treatment in a way that prevents repair, and the inhibition was independent of the number of intercalation sites separating the mismatch and the DNA nick used to direct repair, from 10 to 808 base pairs. Over the broad concentration range tested, there was no evidence for recognition of intercalated adriamycin by MutSalpha as if it were an insertion mismatch. Inhibition apparently results from the ability of the intercalated drug to prevent mismatch binding, shown using a defined mobility shift assay, which occurs at drug concentrations that inhibit repair. These data suggest that adriamycin interacts with the mismatch repair pathway through a mechanism distinct from the manner by which covalent DNA lesions are processed.
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Affiliation(s)
- E D Larson
- Department of Biology, Indiana University, Bloomington 47405, USA
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Affiliation(s)
- C R Hughes
- Department of Biology, University of Miami, Box 249118, Coral Gables, FL 33124-0421, USA.
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