Event:285

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Event Title

Vitellogenin synthesis in liver, Reduction
Short name: Vitellogenin synthesis in liver, Reduction

Key Event Overview

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AOPs Including This Key Event

AOP Name Event Type Essentiality
Aromatase inhibition leading to reproductive dysfunction KE Moderate
Androgen receptor agonism leading to reproductive dysfunction KE Moderate
Estrogen receptor antagonism leading to reproductive dysfunction KE Moderate
Prolyl hydroxylase inhibition leading to reproductive dysfunction via increased HIF1 heterodimer formation KE Moderate
Unknown MIE leading to reproductive dysfunction via increased HIF-1alpha transcription KE

Taxonomic Applicability

Name Scientific Name Evidence Links

Level of Biological Organization

Biological Organization

How this Key Event works

Vitellogenin is an egg yolk precursor protein synthesized by hepatocytes of oviparous vertebrates. In vertebrates, transcription of vitellogenin genes is predominantly regulated by estrogens via their action on nuclear estrogen receptors. During vitellogenic periods of the reproductive cycle, when circulating estrogen concentrations are high, vitellogenin transcription and synthesis are typically orders of magnitude greater than during non-reproductive conditions.

How it is Measured or Detected

Relative abundance of vitellogenin transcripts or protein can be readily measured in liver tissue from organisms exposed in vivo (e.g., (Biales et al. 2007)), or in liver slices (e.g., (Schmieder et al. 2000) or hepatocytes (e.g., (Navas and Segner 2006) exposed in vitro, using real-time quantitative PCR (transcripts) or ELISA (protein).

Evidence Supporting Taxonomic Applicability

Oviparous vertebrates. Although vitellogenin is conserved among oviparous vertebrates and many invertebrates, liver is not a relevant tissue for the production of vitellogenin in invertebrates (Wahli 1988)

References

  • Biales AD, Bencic DC, Lazorchak JL, Lattier DL. 2007. A quantitative real-time polymerase chain reaction method for the analysis of vitellogenin transcripts in model and nonmodel fish species. Environ Toxicol Chem 26(12): 2679-2686.
  • Schmieder P, Tapper M, Linnum A, Denny J, Kolanczyk R, Johnson R. 2000. Optimization of a precision-cut trout liver tissue slice assay as a screen for vitellogenin induction: comparison of slice incubation techniques. Aquat Toxicol 49(4): 251-268.
  • Navas JM, Segner H. 2006. Vitellogenin synthesis in primary cultures of fish liver cells as endpoint for in vitro screening of the (anti)estrogenic activity of chemical substances. Aquat Toxicol 80(1): 1-22.
  • Wahli W. 1988. Evolution and expression of vitellogenin genes. Trends in Genetics. 4:227-232.