Key Event Title
|Level of Biological Organization|
Key Event Components
Key Event Overview
AOPs Including This Key Event
Key Event Description
Sustained AHR/ARNT dimerization induced by DLCs may sequester ARNT from its other dimerization partners at inappropriate times during embryonic cardiomorphogenesis, disrupting ARNT-dependent cellular functions. ARNT serves as a dimerization partner for hypoxia inducible factor 1&alph; (HIF-1α), and this complex is involved in mediating physiological responses to hypoxia. Dimerization between ARNT and HIF-1α forms a transcription factor complex (HIF-1) that binds to hypoxia response enhancer sequences on DNA to activate the expression of genes such as vascular endothelial growth factor (VEGF), which is involved in angiogenesis.
How It Is Measured or Detected
Domain of Applicability
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