The Xenopus Eleutheroembryonic Thyroid Assay (XETA, OECD TG 248) was established as an alternative to the Amphibian Metamorphosis Assay (AMA, OECD TG 231) for the analysis of (anti-)thyroid activity of chemicals. The XETA is a New Approach Method (NAM) since the embryonic life stages used in the assay are not yet feeding independently, which renders the assay to be considered a non-animal test under many national laws. Physiologically, the used embryos are not fully developed yet, and thus there are limitations to the XETA for detecting certain mechanisms along the hypothalamic-pituitary-thyroid (HPT) axis.
View Article and Find Full Text PDFEndoplasmic reticulum (ER) stress, prompted by the accumulation of misfolded or unfolded proteins, triggers the activation of the unfolded protein response (UPR) pathway to restore ER homeostasis. This stress response is implicated in the development of hepatocellular carcinoma (HCC). A biallelic mutation in SPRTN is currently the only known single-gene mutation implicated in the early onset of HCC.
View Article and Find Full Text PDFDNA-protein crosslinks (DPCs), formed by the covalent conjugation of proteins to DNA, are toxic lesions that interfere with DNA metabolic processing and transcription. The development of an accurate biochemical assay for DPC isolation is a priority for the mechanistic understanding of their repair. Here, we propose the STAR assay for the direct quantification of DPCs, sensitive to physiologically relevant treatment conditions.
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October 2023
Histones are an essential part of nucleosomes that regulate chromatin structure and function. Histone exchanges and modifications represent a scaffold for DNA transcription, repair, and replication. Studying histones and histone code is an important and fast-developing branch of epigenetic science.
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