A circadian clock gene, PER2, activates HIF-1 as an effector molecule for recruitment of HIF-1α to promoter regions of its downstream genes
Harada and colleagues (2017), The FEBS Journal, doi: 10.1111/febs.14280
The hypoxia-inducible factor 1 (HIF-1α) is a transcription factor that mediates cellular responses to hypoxia. HIF-1α is known to be upregulated by a component of the circadian clock, the period clock 2 (PER2), but the underlying mechanism was unclear. Harada and colleagues now show that PER2 interacts with HIF-1α and facilitates its recruitment to a hypoxia-response element in the promoter of the vascular endothelial growth factor (VEGF). This PER2-mediated activation occurs in hypoxic conditions and depends on the hydroxylation status of N803 in HIF-1α.
Drinking problems: mechanisms of macropinosome formation and maturation
Buckley and King (2017), The FEBS Journal, doi: 10.1111/febs.14115
Macropinocytosis is the non-specific uptake of extracellular fluid by cells such as macrophages and dendritic cells. It has recently been implicated in the pathogenesis of certain neurodegenerative diseases, atherosclerosis and cancer. In this State-of-the-Art Review, Buckley and King highlight the mechanisms underlying membrane rearrangements during macropinosome formation, the signalling cascades that regulate this process and the future directions in this fast-growing field.