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Abstract BackgroundHistone post-translational modifications (PTMs) are epigenetic marks that can be induced by environmental stress and elicit heritable patterns of gene expression. To investigate this process in an ecological context, we characterized the influence of salinity stress on histone PTMs within the gills, kidney, and testes of Mozambique tilapia (Oreochromis mossambicus). A total of 221 histone PTMs were quantified in each tissue sample and compared between freshwater-adapted fish exposed to salinity treatments that varied in intensity and duration. ResultsFour salinity-responsive histone PTMs were identified in this study. When freshwater-adapted fish were exposed to seawater for two hours, the relative abundance of H1K16ub significantly increased in the gills. Long-term salinity stress elicited changes in both the gills and testes. When freshwater-adapted fish were exposed to a pulse of severe salinity stress, where salinity gradually increased from freshwater to a maximum of 82.5 g/kg, the relative abundance of H1S1ac significantly decreased in the gills. Under the same conditions, the relative abundance of both H3K14ac and H3K18ub decreased significantly in the testes of Mozambique tilapia. ConclusionsThis study demonstrates that salinity stress can alter histone PTMs in the gills and gonads of Mozambique tilapia, which, respectively, signify a potential for histone PTMs to be involved in salinity acclimation and adaptation in euryhaline fishes. These results thereby add to a growing body of evidence that epigenetic mechanisms may be involved in such processes.
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This content will become publicly available on February 11, 2026
Genomes of nine cultured microbes from two hydrologically connected freshwater sites in Wellesley, MA
ABSTRACT We present the genomes of nine cultured microbes isolated from two freshwater sites in Wellesley, MA. The dataset is useful for exploring genomic diversity among freshwater taxa, includingPedobacter,Pseudomonas,Rhodoferax,Rouxiella,andFlavobacterium.
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- Award ID(s):
- 2316244
- PAR ID:
- 10592674
- Editor(s):
- Putonti, Catherine
- Publisher / Repository:
- American Society for Microbiology Microbiology Resource Announcements
- Date Published:
- Journal Name:
- Microbiology Resource Announcements
- Volume:
- 14
- Issue:
- 2
- ISSN:
- 2576-098X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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