Comparing Components of Neuroglobin with Similar Globins

Neuroglobin is a 17‐kDa monomeric oxygen‐binding hemoprotein found in the neurons within the central and peripheral nervous system of mammals and vertebrates. Neuroglobin's structure has been known for twenty years and has been identified in various species. Studies have shown that neuroglobin is responsible for promoting oxygen transportation through blood‐brain barriers, as well as heightening the availability of oxygen in mitochondria. Neuroglobin is responsible for detecting cellular oxygen concentrations like a sensor, and is involved in the detoxification of harmful reactive oxygen. The mechanism of neuroglobin supports neuron survival in hypoxic and ischemic conditions. Neuroglobin additionally enhances cell viability within active cells. For this project the structures, functions, and mechanisms of neuroglobin, hemoglobin, cytoglobin were compared. This comparison was conducted due to each of these molecules’ similarities in properties. Neuroglobin, hemoglobin, and cytoglobin transfer oxygen, but in different manners. Additionally, 20% of Neuroglobin's amino acid sequence homology is expressed in cytoglobin and hemoglobin. It was hypothesized that neuroglobin, which plays an imperative role in the protection and survival of hypoxia and ischemia, is the same protein type as cytoglobin and hemoglobin by having similarities in structure and function, then they will all play a similar role in protecting the human body from these conditions. Through literature review, it was understood that neuroglobin reversibly binds oxygen with a method more efficient than that of hemoglobin and cytoglobin. This is because the majority of cells that neuroglobin is expressed in have an extremely high demand for oxygen. This allows for neuroglobin to be concentrated in a greater amount than hemoglobin and cytoglobin. This ability to increase concentration allows for neuroglobin's overall protection against conditions such as hypoxia and stroke, and for neuroglobin, cytoglobin, and hemoglobin to protect the human body against hypoxic and ischemic conditions. A contrast between the three proteins is the location in which they mainly facilitate oxygen. Although all of these proteins are expressed in the human body, they are found in different regions of it. Neuroglobin is commonly expressed in nerve cells, while cytoglobin is mainly expressed in various tissues at differing levels and hemoglobin is expressed in the red blood cells.