UV-Stressed Daphnia pulex Increase Fitness through Uptake of Vitamin D3

PLoS One. 2015 Jul 6;10(7):e0131847. doi: 10.1371/journal.pone.0131847. eCollection 2015.

Abstract

Ultraviolet radiation is known to be highly variable in aquatic ecosystems. It has been suggested that UV-exposed organisms may demonstrate enough phenotypic plasticity to maintain the relative fitness of natural populations. Our long-term objective is to determine the potential photoprotective effect of vitamin D3 on Daphnia pulex exposed to acute or chronic UV radiation. Herein we report our initial findings in this endeavor. D. pulex survival and reproduction (fitness) was monitored for 5 d as a proof of concept study. Significantly higher fitness was observed in the D. pulex with D3 than those without (most extreme effects observed were 0% survival in the absence of D3 and 100% with 10 ppm D3). Vitamin D3 was isolated from the culture media, the algal food (Pseudokirchneriella), and the D. pulex and quantified using high performance liquid chromatography (HPLC). Vitamin D3 was fluorescently labeled using a phenothiazinium dye and added to cultures of D. pulex. Images demonstrating the uptake of D3 into the tissues and carapace of the D. pulex were acquired. Our initial findings suggest a positive role for D3 in ecosystems as both UV-stressed algae and Daphnia sequester D3, and D. pulex demonstrate increased fitness in the presence of D3.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cholecalciferol / metabolism*
  • Chromatography, High Pressure Liquid
  • Daphnia / metabolism
  • Daphnia / physiology
  • Daphnia / radiation effects*
  • Ecosystem
  • Microalgae / metabolism
  • Ultraviolet Rays*

Substances

  • Cholecalciferol

Grants and funding

The authors received funding to support from the following entities within Rochester Institute of Technology: College of Science (RIT) Faculty Development Awards; the College of Science (RIT) Undergraduate Summer Scholars Fellowship Awards; the RIT Honors Program Undergraduate Student Summer Scholarship Award; the RIT Ronald E. McNair Post-Baccalaureate Achievement Program; the RIT School of Chemistry and Materials Science Dr. Terry Morrill Endowed Student Research Fund; the RIT School of Chemistry and Materials Science Daniel Pasto Award; the RIT Office of Sponsored Research Sponsored Research Grants; the RIT School of Chemistry and Materials Science; the Thomas H. Gosnell School of Life Sciences; and the National Science Foundation Major Research Instrumentation Program (#1126629). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.