Poldip2 is an oxygen-sensitive protein that controls PDH and αKGDH lipoylation and activation to support metabolic adaptation in hypoxia and cancer. Paredes et al.
By performing hypoxic studies in their Whitley H35 Hypoxystation on a variety of cell lines, researchers at Emory University in Atlanta, Georgia have found that a protein with a previously unknown function (polymerase -δ interacting protein 2 (poldip2)) actually plays a key role in mitochondrial function and cell metabolism. They have shown that lipoylation of pyruvate dehydrogenase and α-ketoglutarate dehydrogenase (αKDH) complexes is a dynamically regulated process that is inhibited under hypoxia and in cancer cells to restrain mitochondrial respiration.
By exposing cells to varying degrees of oxygen tensions in their H35, they were able to show that poldip2 is down-regulated by hypoxia. In addition, they were able to show that by forced expression of Poldip2, respiration increased and the growth rate of cancer cells decreased. Further work needs to be done with Poldip2 especially in discovering its relationship with HIF-1α, however this work is a great addition to the body of knowledge we have about tumour metabolism. All this is thanks to the researchers at Emory University and their H35 Hypoxystation. To view the paper, click here.