Dimethylsulfoniopropionate (
Armored skin resulting from the presence of bony dermal structures, osteoderms, is an exceptional phenotype in gekkotans (geckos and flap‐footed lizards) only known to occur in three genera:
- NSF-PAR ID:
- 10458571
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Morphology
- Volume:
- 281
- Issue:
- 2
- ISSN:
- 0362-2525
- Page Range / eLocation ID:
- p. 213-228
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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DMSP ) is produced by many species of marine phytoplankton and has been reported to provide a variety of beneficial functions including osmoregulation. Dinoflagellates are recognized as majorDMSP producers; however, accumulation has been shown to be highly variable in this group. We explored the effect of hyposaline transfer inGambierdiscus belizeanus between ecologically relevant salinities (36 and 31) onDMSP accumulation, Chla , cell growth, and cell volume, over 12 d. Our results showed thatG. belizeanus maintained an intracellularDMSP content of 16.3 pmol cell−1and concentration of 139mM in both salinities. Although this intracellular concentration was near the median reported for other dinoflagellates, the cellular content achieved byG. belizeanus was the highest reported of any dinoflagellate thus far, owing mainly to its large size.DMSP levels were not significantly affected by salinity treatment but did change over time during the experiment. Salinity, however, did have a significant effect on the ratio ofDMSP :Chla , suggesting that salinity transfer ofG. belizeanus induced a physiological response other thanDMSP adjustment. A survey ofDMSP content in a variety ofGambierdiscus species and strains revealed relatively highDMSP concentrations (1.0–16.4 pmol cell−1) as well as high intrageneric and intraspecific variation. We conclude that, althoughDMSP may not be involved in long‐term (3–12 d) osmoregulation in this species,G. belizeanus and otherGambierdiscus species may be important contributors toDMSP production in tropical benthic microalgal communities due to their large size and high cellular content. -
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