Disease relevance of Mars

• The risk of radiation-induced cancer to space travelers outside the earth's magnetosphere will be of concern on missions to the Moon and beyond to Mars [1].
• According to this hypothesis, metabolic conversion of Hcy to a chemically reactive metabolite, Hcy-thiolactone, catalyzed by methionyl-tRNA synthetase is the first step in a pathway that contributes to Hcy toxicity in humans [2].

High impact information on Mars

• Half of the genes found to be upregulated are involved in transport and biosynthesis of amino acids, including several amino acid transport proteins, argininosuccinate and asparagine synthetases, and methionyl-tRNA synthetase [3].
• With further development of these approaches, it may be feasible to monitor changes in gene expression after low-dose radiation exposure and other physiological stresses that may be encountered during manned space flight, such as the planned mission to Mars [4].
• CHOP/GADD153 and methionyl-tRNA synthetase (MetRS) genes overlap in a conserved region that controls mRNA stability [5].
• Transfection experiments in NIH-3T3 cells show that CHOP 3'UTR confers a significantly lower activity than a control reporter or a reporter in which the region overlapping the MetRS mRNA is deleted [5].
• Because radiation can cause hyperploidy, an increase of DNA content in cells, and can induce DNA rearrangement, it is likely that the evolution of life on Mars will be effected by its radiation environment [6].

Biological context of Mars

• The conservation of this overlapping of the CHOP and MetRS genes and the role of their complementary sequence in the control of mRNA stability suggest the existence of a functional link between the expression of these two genes [5].

References