Kennesaw State University
The HV1 proton channel of Lingulodinium polyedrum localizes to the bioluminescent scintillon
Abstract
dc:description.abstract<p>In 1972, J. Woodland Hastings and colleagues predicted the existence of a proton selective channel that opens in response to depolarizing voltage (H<sub>V</sub>1) across the vacuole membrane of bioluminescent dinoflagellates and conducts protons into specialized luminescence compartments (scintillons), thus causing the pH drop that triggers the light flash. RNA-Seq data from several luminescent dinoflagellate species provided candidate H<sub>V</sub>1 genes. When expressed in mammalian cells, the predicted H<sub>V</sub>1 from <em>Lingulodinium polyedrum </em>displays the hallmark properties of bona fide proton channels, including time-dependent opening with depolarization, perfect proton selectivity, and characteristic pH dependent gating. RT-PCR and Western blotting confirm expression of H<sub>V</sub>1 in <em>L. polyedrum</em> and isolated scintillons. Fluorescence confocal microscopy of <em>L. polyedrum </em>cells stained with antibodies to luminescence proteins luciferase (LCF), luciferin binding protein (LBP) and to H<sub>V</sub>1 (LpH<sub>V</sub>1) reveal structures consistent with H<sub>V</sub>1’s proposed function in bioluminescence. Isolated scintillons immunostained with antibody to LpH<sub>V</sub>1 displayed LpH<sub>V</sub>1 expression, showing that LpH<sub>V</sub>1 is present in this organelle. In addition, proteomics analysis demonstrated that isolated scintillon preparations contain peptides that map to LpH<sub>V</sub>1, including a portion of the epitope used to raise the antibody. These results indicate that LpH<sub>V</sub>1 is the voltage gated proton channel that triggers bioluminescence in <em>L. polyedrum</em>.</p>
Degree
thesis:*- Name thesis:degree_name
- Master of Science in Integrative Biology (MSIB)
- Level thesis:degree_level
- Thesis
- Discipline thesis:degree_discipline
- Biology
- Year dc:date.available
- 2016
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Rodriguez, Juan D.
- Contributors dc:contributor
-
- Susan M.E. Smith
- Donald J. McGarey
- Scott J. Nowak
Subjects
dc:subject × 7Identifiers
dc:identifier.*- Repository record dc:identifier
- https://digitalcommons.kennesaw.edu/integrbiol_etd/10
- OAI identifier oai:identifier
- oai:digitalcommons.kennesaw.edu:integrbiol_etd-1009