Hypoxia-inducible factor 3 alpha is a protein that in humans is encoded by the HIF3A gene.
Function
The protein encoded by this gene is the alpha-3 subunit of one of several alpha/beta-subunit heterodimeric transcription factors that regulate many adaptive responses to low oxygen tension (hypoxia). The alpha-3 subunit lacks the transactivation domain found in factors containing either the alpha-1 or alpha-2 subunits. It is thought that factors containing the alpha-3 subunit are negative regulators of hypoxia-inducible gene expression. At least three transcript variants encoding three different isoforms have been found for this gene.
In rats, it plays a negative role in the adaptation to hypoxia, because the inhibition of HIF-3α expression leads to an increase in physical endurance.
Clinical significance
DNA methylation in the introns of HIF3A is associated with BMI an adiposity.