Diatom transcriptional and physiological responses to changes in iron bioavailability across ocean provinces Public Deposited

Downloadable Content

Download PDF
Creator
  • Cohen, N.R.
    • Affiliation: College of Arts and Sciences, Department of Marine Sciences
  • Ellis, K.A.
    • Affiliation: College of Arts and Sciences, Department of Marine Sciences
  • Lampe, R.H.
    • Affiliation: College of Arts and Sciences, Department of Marine Sciences
  • McNair, H.
    • Other Affiliation: University of California, Santa Barbara
  • Twining, B.S.
    • Other Affiliation: Bigelow Laboratory for Ocean Sciences
  • Maldonado, M.T.
    • Other Affiliation: University of British Columbia
  • Brzezinski, M.A.
    • Other Affiliation: University of California, Santa Barbara
  • Kuzminov, F.I.
    • Other Affiliation: Rutgers, The State University of New Jersey
  • Thamatrakoln, K.
    • Other Affiliation: Rutgers, The State University of New Jersey
  • Till, C.P.
    • Other Affiliation: University of California, Santa Cruz
  • Bruland, K.W.
    • Other Affiliation: University of California, Santa Cruz
  • Sunda, W.G.
    • Affiliation: College of Arts and Sciences, Department of Marine Sciences
  • Bargu, S.
    • Other Affiliation: Louisiana State University
  • Marchetti, A.
    • Affiliation: College of Arts and Sciences, Department of Marine Sciences
Abstract
  • Changes in iron (Fe) bioavailability influence diatom physiology and community composition, and thus have a profound impact on primary productivity and ecosystem dynamics. Iron limitation of diatom growth rates has been demonstrated in both oceanic and coastal waters of the Northeast Pacific Ocean and is predicted to become more pervasive in future oceans. However, it is unclear how the strategies utilized by phytoplankton to cope with low Fe bioavailability and resupply differ across these ocean provinces. We investigated the response of diatom communities to variable Fe conditions through incubation experiments performed in the Fe mosaic of the California Upwelling Zone and along a natural Fe gradient in the Northeast Pacific Ocean. Through coupling gene expression of two dominant diatom taxa (Pseudo-nitzschia and Thalassiosira) with biological rate process measurements, we provide an in-depth examination of the physiological and molecular responses associated with varying Fe status. Following Fe enrichment, oceanic diatoms showed distinct differential expression of gene products involved in nitrogen assimilation, photosynthetic carbon fixation, and vitamin production compared to diatoms from low-Fe coastal sites, possibly driven by the chronic nature of Fe stress at the oceanic site. Genes of interest involved in Fe and N metabolism additionally exhibited divergent expression patterns between the two diatom taxa investigated, demonstrating that diverse diatoms may invoke alternative strategies when dealing with identical changes in their environment. We report here several mechanisms used distinctly by coastal or oceanic diatom communities as well as numerous taxa-specific strategies for coping with Fe stress and rearranging nutrient metabolism following Fe enrichment.
Date of publication
Keyword
DOI
Identifier
Resource type
  • Article
Rights statement
  • In Copyright
License
  • Attributon 4.0 International
Journal title
  • Frontiers in Marine Science
Journal volume
  • 4
Journal issue
  • NOV
Language
  • English
Version
  • Publisher
ISSN
  • 2296-7745
Publisher
  • Frontiers Media S. A
Parents:

This work has no parents.

In Collection:

Items