Neuroglobin
Neuroglobin (Ngb), a monomeric globin expressed in the central and peripheral nervous systems of vertebrates, is of interest because of its neuroprotective properties. In vitro and in vivo assays show that elevated levels of Ngb protect neural tissues under hypoxic conditions; the neuroprotective effect of Ngb upon acute brain injury can last for up to two weeks. However, the mechanism for this protective activity is uncertain, although several postulates have been put forward, and it has been shown that human Ngb possesses a redox-regulated switch that is presumably implicated in its activity. Our investigations include the mechanism of the redox switching process, the transfer of information from the enzyme’s surface to the active site, and the relationship between structural and functional variations in neuroglobin across species. The cartoon above relates release of ROS (reactive oxygen species) by mitochondria under hypoxic conditions to a redox-switched-induced conformation change in hNgb.