The HIF-1 alpha-C/EBP alpha axis.

The hypoxia inducible factors (HIFs) and CCAAT/enhancer binding protein alpha (C/EBP alpha) are transcription factors that mediate adaptive responses to hypoxia and control aspects of energy metabolism, respectively. New evidence suggests that when HIF-1 alpha and C/EBP alpha interact, they bring about reciprocal functional changes, so that the activity of HIF-1 alpha is decreased and that of C/EBP alpha is restricted or increased in a tissue-specific manner. This Journal Club article highlights research depicting interactions between HIF-1 alpha and C/EBP alpha and discusses conditions and tissues in which this interaction might occur.