Diverse biophysical and molecular mechanisms drive phytoplankton sinking in response to starvation
Name
journal.pbio.3003508.pdf
Description
Published version
Size
2.09 MB
Format
Adobe PDF
Checksum (MD5)
1aaa1e01b8788572e5fd271fc98498d9
Author(s)
Wu, Yanqi
Kouadio, Vieyiti K
Usherwood, Thomas R
Li, Justin
Bisher, Margaret
Aurora, Reshum
Lam, Aaron Z
Lam, Alice R
Lytton-Jean, Abigail KR
Manalis, Scott R
Date Issued
November 19, 2025
Journal
PLOS Biology
Publisher
Public Library of Science (PLoS)
Citation
Wu Y, Kouadio VK, Usherwood TR, Li J, Bisher M, et al. (2025) Diverse biophysical and molecular mechanisms drive phytoplankton sinking in response to starvation. PLOS Biology 23(11): e3003508.
Version
Final published version
Abstract
Marine phytoplankton face eco-evolutionary pressure to regulate their vertical position in the ocean to access light, which is abundant towards the surface, and nutrients, which are found deeper down the water column. All phytoplankton experience gravitational sinking, which can contribute to their vertical migration. However, the biophysical and molecular mechanisms that impact gravitational sinking have not been systematically characterized across taxa and environmental conditions. Here, we combine simulations with measurements of cell mass, volume, and composition to investigate the effects of nutrient availability on gravitational sinking in nine representative unicellular pico- and nanoplankton species. We find that gravitational sinking becomes faster in most species when starved, but the biophysical changes responsible for this vary across species and starvation conditions. For example, the faster sinking of Chaetoceros calcitrans is nearly exclusively driven by cell density whereas that of Emiliania huxleyi is due to cell volume. On the molecular level, the altered sinking is predominantly attributed to changes in cellular dry contents, rather than water. For example, starch accumulation increases sinking in three green algae species, and lipid accumulation decreases sinking in Phaeodactylum tricornutum. Overall, our work reveals that phytoplankton physiology has evolved multiple mechanisms that impact gravitational sinking in response to starvation, possibly to support the vertical migration of the cell.
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1371/journal.pbio.3003508
