Abstract
FAHD1 is a mitochondrial enzyme involved in oxaloacetate metabolism, with emerging links to cellular redox balance, Ca2+-metabolism, and structural features. Building on previous work (Heberle et al. Sci Rep 14:9231, 2024), we investigated how overexpression of human FAHD1 (hFAHD1) variants, including wild-type, the catalytically inactive hFAHD1-K123A, and the hyperactive hFAHD1-T192S, affects nuclear morphology in U2OS osteosarcoma cells. Using high-content microscopy and automated classification, we observed variant-specific shifts in nuclear shape distributions. Notably, expression of K123A was associated with a higher frequency of large, rounded nuclei and a reduction in elongated forms, while the T192S variant produced subtler changes. By aligning morphological clusters with available proteomic profiles, we identified suggestive correlations with differences in biosynthetic activity and chromatin organization. These findings indicate that altered FAHD1 activity is correlated with changes in nuclear morphology and may be associated with broader cellular organization. Our results are descriptive and hypothesis-generating, highlighting possible links between mitochondrial metabolic states and nuclear architecture that warrant further validation.
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Data files and full statistical data evaluation are available from the corresponding author upon reasonable request.
Abbreviations
- FAHD1:
-
Fumarylacetoacetate hydrolase domain-containing protein 1
- hFAHD1:
-
Human fumarylacetoacetate hydrolase domain-containing protein 1
- TCA cycle:
-
Tricarboxylic acid cycle
- ROS:
-
Reactive oxygen species
- WT:
-
Wild type
- K123A:
-
FAHD1 variant with lysine at position 123 replaced by alanine
- T192S:
-
FAHD1 variant with threonine at position 192 replaced by serine
- CTRL:
-
Control (unmodified U2OS cells)
- U2OS:
-
Human osteosarcoma cell line
- PBS:
-
Phosphate-buffered saline
- FCS:
-
Fetal calf serum
- DMEM:
-
Dulbecco’s modified eagle medium
- BIAS:
-
Biological image analysis software
- DRAQ5:
-
DNA intercalating fluorescent dye
- CV1000:
-
CellVoyager 1000 high-content screening microscope
- ImageStream:
-
Amnis® ImageStream®X MkII imaging flow cytometer
- MS/MS:
-
Tandem mass spectrometry
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AP: Conceptualization, Methodology, Investigation, Formal Analysis, Visualization. AH: Cell line generation, Methodology. AW: Conceptualization, Supervision, Writing, Review & Editing, Project Administration.
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Pfarl, A.S., Heberle, A. & Weiss, A.K.H. Catalytic activity of FAHD1 correlates with nuclear morphology and proteomic states in human osteosarcoma cells. Sci Rep (2025). https://doi.org/10.1038/s41598-025-29460-x
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DOI: https://doi.org/10.1038/s41598-025-29460-x
