How decreasing oxygenase activity helps cells cope with hypoxia

Abstract

The ability of our bodies to adapt to reduced oxygen availability (hypoxia) by increasing red blood cell formation was recognized in the 19th century, but almost 200 years passed before the molecular mechanism underlying this hypoxic response was revealed. In animals, hypoxia tolerance is enabled by turning on a plethora of genes, all under the control of the hypoxia inducible transcription factor protein, HIF. Crucially, levels of HIF are controlled by a set of enzymes, whose activity is exquisitely sensitive to oxygen availability. A low-oxygen response system is arguably more important for plants which, as sessile organisms, cannot employ behavioural responses to hypoxia, and recent findings reveal a distinct yet analogous mechanism. It seems that in plants as well as in animals, oxygen-dependent enzymes are the linchpins connecting oxygen availability with the cellular response to hypoxia.