Retinal responses during exposure to decreasing oxygen partial pressure (pO2)

Website: https://www.bco-dmo.org/dataset/779540
Data Type: experimental
Version: 1
Version Date: 2019-10-23

Project
» Vision-mediated influence of low oxygen on the physiology and ecology of marine larvae (Vision under hypoxia)
ContributorsAffiliationRole
Levin, Lisa A.University of California-San Diego (UCSD)Principal Investigator
Oesch, NicholasUniversity of California-San Diego (UCSD)Co-Principal Investigator

Abstract
Retinal responses during exposure to decreasing oxygen partial pressure (pO2) in marine invertebrate larvae determined with electroretinograms.


Dataset Description

Retinal responses during exposure to decreasing oxygen partial pressure (pO2) in marine invertebrate larvae determined with electroretinograms.

Please see additional datasets for this paper, including the “OxygenMetrics_Vision” and the “Experiment_Metrics” datasets.


Acquisition Description

Detailed methods can be found in McCormick et al., 2019

Briefly, the time series test recorded electroretinogram (ERG) responses to a 1 s square step of light at a constant irradiance of 3.56 μmol photons m2 s1 repeated every 20 s, providing a nearly continuous measure of ERG response in a tethered, live larva during the experimental manipulation of partial pressure of oxygen (pO2). There was a constant flow of pH-buffered sterile seawater in the chamber where the larva was held, and after a brief period in “normoxia” (surface-ocean oxygen levels), the pO2 was decreased, and then held at a low pO2 before re-oxygenating the solution.

This dataset shows the retinal responses measured every 20 s for all individuals used in Figure 1 (top panel) of McCormick et al., 2019. The retinal responses show a decline in retinal function during a decrease in oxygen availability.

Oxygen was measured using a Microx4 (PreSens) oxygen meter and a Pst-7 oxygen optode probe.


Processing Description

All electrophysiology data was recorded and analyzed using Igor Pro 7 Software (Wavemetrics) using custom code. Oxygen data was analyzed using PreSens Measurement Studio 2. Post-processing analysis was completed in R Studio (version 3.3.3).


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Related Publications

McCormick, L. R., Levin, L. A., & Oesch, N. W. (2019). Vision is highly sensitive to oxygen availability in marine invertebrate larvae. The Journal of Experimental Biology, 222(10), jeb200899. doi:10.1242/jeb.200899
Methods

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Parameters

ParameterDescriptionUnits
SpeciesSpecies name. Format is "Species_genus". unitless
Experiment_NameOriginal experiment name that can be linked back to raw datafile collected in Igor. unitless
RoundThe number of seconds since starting each individual experiment. unitless
O2_umol_lOxygen concentration in umol O2/L for each retinal measurement. micromole per liter (umol/L)
O2_ml_lOxygen concentration in mL O2/L for each retinal measurement. milliliter per liter (ml/l)
O2_umol_kgOxygen concentration in umol O2/kg for each retinal measurement. micromole per kg (umol/kg)
O2_pO2The partial pressure of oxygen of the given metric “n.ctrl.area”: The ERG response normalized to the average retinal response measured during exposure to normoxia. kiloPascal (kPa)
n_ctrl_areaThe integration of the ERG wave at any given time divided by the average integrated ERG during control oxygen conditions. Normalization was done to compare between individuals and species. unitless
RunningAvgThe running average of retinal responses in the last minute, used to show smoothed responses over time. unitless
RunAvgLineThe line number for the running average, used to order measurements within an individual experiment. unitless
ConditionOxygen exposure during the experiment, either "normoxia", “decrease”, or “Low”. First, animals were exposed to “normoxia” (~100-105% oxygen saturation), then a “Deacrease” in oxygen (slow decline of oxygen), until the “Low” oxygen was reached. unitless


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Instruments

Dataset-specific Instrument Name
Generic Instrument Name
Oxygen Microelectrode Sensor
Dataset-specific Description
Oxygen was measured using a Microx4 (PreSens) oxygen meter and a Pst-7 oxygen optode probe.
Generic Instrument Description
Any microelectrode sensor that measures oxygen.


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Project Information

Vision-mediated influence of low oxygen on the physiology and ecology of marine larvae (Vision under hypoxia)

Coverage: Southern California Bight, Northeast Pacific Ocean


NSF abstract:
Oxygen is being lost in the ocean worldwide as a result of ocean warming and the input of nutrients from land. Vision requires a large amount of oxygen, and may be less effective or require more light when oxygen is in short supply. This is especially true for active marine animals with complex eyes and visual capabilities, including active arthropods (crabs), cephalopods (squid), and fish. The California coastal waters exhibit a sharp drop in oxygen and light with increasing water depth. This project examines how visual physiology and ecology in young (larval) highly visual marine animals respond to oxygen loss, with a focus on key fisheries and aquaculture species. Experiments and observations will test the hypothesis that oxygen stress will change the light required for these organisms to see effectively, influencing the water depths where they can live and survive. The project will provide interdisciplinary experiences to students and an early career scientist and inform both the public (through outreach at the Birch Aquarium at Scripps Institution of Oceanography) and policy makers about the effects of oxygen decline in the ocean.

Negative effects of oxygen loss on vision have been described for humans and other terrestrial organisms, but never in the marine environment, despite the large changes in oxygen that can occur with depth and over time in the ocean, and the high metabolic demand of visual systems. This project will test the effects of low oxygen on vision in 3 combinations of eye design and photo-transduction mechanisms: compound eye with rhabdomeric photoreceptors (arthropods), simple eye with rhabdomeric photoreceptors (cephalopods), and simple eye with ciliary photoreceptors (fish). A series of oxygen- and light-controlled laboratory experiments will be conducted on representative taxa of each group including the tuna crab, Pleuroncodes planipes; the market squid, Doryteuthis opalescens, and the white sea bass, Atractoscion nobilis. In vivo electrophysiology and behavioral phototaxis experiments will identify new oxygen metrics for visual physiology and function, and will be compared to metabolic thresholds determined in respiration experiments. Hydrographic data collected over 3 decades by the CalCOFI program in the Southern California Bight will be evaluated with respect to visual and metabolic limits to determine the consequences of oxygen variation on the critical luminoxyscape (range of oxygen and light conditions required for visual physiology and function in target species) boundary in each species. Findings for the three vision-based functional groups may test whether oxygen-limited visual responses offer an additional explanation for the shoaling of species distributions among highly visual pelagic taxa in low oxygen, and will help to focus future research efforts and better understand the stressors contributing to habitat compression with expanding oxygen loss in the ocean.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.



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Funding

Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)

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