Vitamin K2 Is a Mitochondrial Electron Carrier That Rescues Pink1 Deficiency

Pink1 is a mitochondrial kinase, and loss of Pink1 function in flies and mice results in the accumulation of inefficient mitochondria. In a screen for modifiers of the Parkinson-associated gene, pink1 , Vos et al. (p. [1306][1], published online 10 May; see the Perspective by [Bhalerao and Clandinin][2] ) identified the fruit fly homolog of UBIAD1, “Heix.” UBIAD1 was localized in mitochondria and was able to convert vitamin K1 into vitamin K2/menaquinone (MK- n, n the number of prenylgroups). In bacteria, vitamin K2/MK- n acts as an electron carrier in the membrane and, similarly, in Drosophila , mitochondrial vitamin K2 appeared to act as an electron carrier to facilitate adenosine triphosphate production. Fruit flies that lack heix showed severe mitochondrial defects that could be rescued by administering vitamin K2. [1]: /lookup/doi/10.1126/science.1218632 [2]: /lookup/volpage/336/1241?iss=6086