Adaptation to hypoxia is an essential cellular response controlled by the oxygen-sensitive master transcription factor hypoxia-inducible factor 1 (HIF-1). HIF-1 expression is also controlled by specific microRNAs and, in turn, controls the expression of other microRNAs, which fine-tune adaptation to low oxygen tension. In this issue of the JCI, Ghosh and colleagues identify a unique microRNA in hypoxic endothelial cells, miR424, that promotes HIF-1 stabilization and angiogenesis. The actions of this microRNA are considered in the context of the complex interactions that act to ensure optimal endothelial adaptation to this critical environmental condition.
The endothelial cell response to hypoxia.