title: ASIC1-mediated calcium entry stimulates NFATc3 nuclear translocation via PICK1 coupling in pulmonary arterial smooth muscle cells.
abstract: The development of chronic hypoxia (CH)-induced pulmonary hypertension is associated with increased pulmonary arterial smooth muscle cell (PASMC) Ca(2+) influx through acid-sensing ion channel-1 (ASIC1) and activation of the Ca(2+)/calcineurin-dependent transcription factor known as nuclear factor of activated T-cells isoform c3 (NFATc3). Whether Ca(2+) influx through ASIC1 contributes to NFATc3 activation in the pulmonary vasculature is unknown. Furthermore, both ASIC1 and calcineurin have been shown to interact with the scaffolding protein known as protein interacting with C kinase-1 (PICK1). In the present study, we tested the hypothesis that ASIC1 contributes to NFATc3 nuclear translocation in PASMC in a PICK1-dependent manner. Using both ASIC1 knockout (ASIC1(-/-)) mice and pharmacological inhibition of ASIC1, we demonstrate that ASIC1 contributes to CH-induced (1 wk at 380 mmHg) and endothelin-1 (ET-1)-induced (10(-7) M) Ca(2+) responses and NFATc3 nuclear import in PASMC. The interaction between ASIC1/PICK1/calcineurin was shown using a Duolink in situ Proximity Ligation Assay. Inhibition of PICK1 by using FSC231 abolished ET-1-induced and ionomycin-induced NFATc3 nuclear import, but it did not alter ET-1-mediated Ca(2+) responses, suggesting that PICK1 acts downstream of Ca(2+) influx. The key findings of the present work are that 1) Ca(2+) influx through ASIC1 mediates CH- and ET-1-induced NFATc3 nuclear import and 2) the scaffolding protein PICK1 is necessary for NFATc3 nuclear import. Together, these data provide an essential link between CH-induced ASIC1-mediated Ca(2+) influx and activation of the NFATc3 transcription factor. Identification of this ASIC1/PICK1/NFATc3 signaling complex increases our understanding of the mechanisms contributing to the vascular remodeling and increased vascular contractility that are associated with CH-induced pulmonary hypertension.
authors.affiliation: Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico.
authors.forename: Laura V
authors.initials: LV
authors.lastname: Gonzalez Bosc
authors.affiliation: Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico.
authors.forename: Danielle R
authors.initials: DR
authors.lastname: Plomaritas
authors.affiliation: Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico.
authors.forename: Lindsay M
authors.initials: LM
authors.lastname: Herbert
authors.affiliation: Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico.
authors.forename: Wieslawa
authors.initials: W
authors.lastname: Giermakowska
authors.affiliation: Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico.
authors.forename: Carly
authors.initials: C
authors.lastname: Browning
authors.affiliation: Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, New Mexico njernigan@salud.unm.edu.
authors.forename: Nikki L
authors.initials: NL
authors.lastname: Jernigan
mesh_terms: D062565:Acid Sensing Ion Channels / Q000502:physiology*; D021581:Active Transport, Cell Nucleus; D000818:Animals; D020013:Calcium Signaling; D002352:Carrier Proteins / Q000378:metabolism*; D018797:Cell Cycle Proteins; D015687:Cell Hypoxia; D002478:Cells, Cultured; D019332:Endothelin-1 / Q000502:physiology; D005260:Female; D006976:Hypertension, Pulmonary / Q000378:metabolism; D008297:Male; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009131:Muscle, Smooth, Vascular / Q000473:pathology; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D050778:NFATC Transcription Factors / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism*; D011651:Pulmonary Artery / Q000473:pathology
chemical_list: C568267:ASIC1 protein, mouse; D062565:Acid Sensing Ion Channels; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D019332:Endothelin-1; D050778:NFATC Transcription Factors; C494009:Nfatc3 protein, mouse; D009687:Nuclear Proteins; C091822:Prkcabp protein, mouse
keywords: calcineurin; endothelin-1; hypoxia; pulmonary hypertension; store-operated calcium