Proteome of Dried Blood Spots of Cosmonauts during a 6-Month Flight

For successful exploration of near space, construction of planetary bases and exploration of the Solar System planets, it is necessary to fill the gaps in understanding the molecular mechanisms of the human body response to space flight (SF) conditions. Subsequently, this will make it possible to get closer to the discovery of potential molecular targets for protection against adverse processes occurring in the body under the influence of SF conditions. The aim of the work was to assess the effect of a 6-month space flight on the proteome of dried blood spots of cosmonauts. As a result of proteomic analysis, processes with highly and moderately enriched proteins were identified. Among them, processes with reliable dynamics were identified on the 7th day of SF, as well as on the 3rd and 6th months of flight: these are clusters of energy processes, presentation of molecules on the membrane, initiation of immune defense, proteostasis and metabolism. Biological processes were identified in which the representation of proteins decreased most significantly, which was reflected in a weakening of activity in the presentation of molecules on the membrane, the initiation of immune defense, as well as in the mechanisms of proteostasis in the acute period of adaptation to the factors of the initial stage of flight. It has been shown that there is a close interaction with proteins of the cytoskeleton organization that disappear or reappear in the dried blood spots proteome during flight, and that relate to processes whose activity significantly decreased during SF (immune system, proteostasis, metabolism).