Investigating the possibility of life surviving in extraterrestrial conditions is an important goal of astrobiology. In the new study, scientists used baker's yeast, a powerful model organism, to evaluate the effects of Martian-like conditions; they observed that the yeast withstood shock waves and perchlorate treatment, two stressors relevant to Mars; in addition, the yeast responds to Martian conditions by assembling conserved RNA-protein complexes.
Model showing the importance of RNP condensate in ensuring survival in stressful conditions like those found on Mars. Image credit: Dhage etc.., doi: 10.1093/pnasnexus/pgaf300.
“With advances in space science and astrobiology, studying the potential of Mars to support life forms is receiving significant attention,” said Dr Purusharth Rajyaguru of the Indian Institute of Science and colleagues.
“Mars offers a number of hostile environmental conditions that potential life forms would have to overcome.”
“Thus, understanding its unique and complex environmental conditions becomes important.”
“Martian stress conditions are characterized by the following: (i) high-intensity shock waves resulting from meteorite impacts, (ii) extreme fluctuations in temperature and pressure, (iii) ionizing and solar ultraviolet radiation due to a thin atmosphere, and (iv) chaotropic agents such as perchlorates.”
“These conditions pose a serious obstacle to survival potential life forms“
During the study, the authors subjected Saccharomyces cerevisiaewhich is a widely used yeast model for shock waves and perchlorates.
They chose yeast in part because it had already been studied in space.
Under stress, yeast, humans, and many other organisms form ribonucleoprotein condensates (RNPs), structures made of RNA and proteins that protect the RNA and influence the fate of the mRNA.
When the stressor passes, RNPs condense, including subtypes known as stress granules and P-bodies, disassemble.
Yeast exposed to Mach 5.6 shock waves survived with reduced growth, as did yeast exposed to 100 mM sodium perchlorate (NaClO4) – concentration similar to Martian soil.
The yeast cells also withstood shock waves and perchlorate stress.
In both cases, the yeast collects RNP condensates, the team says.
The shock waves caused the assembly of stress granules and P-bodies; perchlorate caused the yeast to produce P-bodies but not stress granules.
Mutants unable to collect RNP condensates did not survive Martian stress conditions well.
Transcriptomic analysis revealed specific RNA transcripts disrupted by Martian-like conditions.
“The results demonstrate the importance of yeasts and RNP condensates in understanding the impact of Martian conditions on life,” the scientists concluded.
Their paper appears in the magazine today PNAS Nexus.
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Riya Dhage etc.. 2025. Ribonucleoprotein (RNP) condensates modulate survival in response to Martian-like stress conditions. PNAS Nexus 4 (10): pgaf300; doi: 10.1093/pnasnexus/pgaf300
