Binding of Erythrocyte Hemoglobin to the Membrane to Realize Signal-Regulatory Function (Review)

Resumo

Reversible protein binding with membrane components and the cytoskeleton is one of mechanisms of cell metabolism control. This is a crucial mechanism for the regulation of metabolism in nuclear-free cells, mammal erythrocytes, in which it is realized via hemoglobin modification to the membrane-bound state. Hemoglobin can interact with the membrane in different ligands and redox statuses. Thus, this protein can function as a sensor of redox and oxygen conditions. Depending on the oxygen conditions, deoxyHb changes the energetic metabolism, morphology, and deformability of erytrocytes, as well as the release of vascular tone regulators, NO and ATP. This is fulfilled via interaction with the main integral protein of erythrocyte membrane, the band 3 protein. The products of hemoglobin oxidative denaturation, irreversible hemichromes, also carry out a signaling function. Accumulating over time or as result of oxidative stress, chemichromes contain information on the redox conditions and the longevity of erythrocyte functioning. It has been hypothesized that erythrocytes have a program that initiates intracellular hemolysis. The participation of hemoglobin and its membrane-bound form (MBHb) in the realization of this program is discussed. The role of NO donors in the regulation of erythrocyte stability is debated as well. The use of data on the MBHb content in erythrocytes is proposed for clinical diagnostics.