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Warmer temperatures enhance beneficial mutation effects.

ABSTRACT: Temperature determines the rates of all biochemical and biophysical processes, and is also believed to be a key driver of macroevolutionary patterns. It is suggested that physiological constraints at low temperatures may diminish the fitness advantages of otherwise beneficial mutations; by contrast, relatively high, benign, temperatures allow beneficial mutations to efficiently show their phenotypic effects. To experimentally test this "mutational effects" mechanism, we examined the fitness effects of mutations across a temperature gradient using bacterial genotypes from the early stage of a mutation accumulation experiment with Escherichia coli. While the incidence of beneficial mutations did not significantly change across environmental temperatures, the number of mutations that conferred strong beneficial fitness effects was greater at higher temperatures. The results therefore support the hypothesis that warmer temperatures increase the chance and magnitude of positive selection, with implications for explaining the geographic patterns in evolutionary rates and understanding contemporary evolution under global warming.

SUBMITTER: Chu XL

PROVIDER: S-EPMC7496171 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Warmer temperatures enhance beneficial mutation effects.

Chu Xiao-Lin XL Zhang Da-Yong DY Buckling Angus A Zhang Quan-Guo QG

Journal of evolutionary biology 20200623 8

Temperature determines the rates of all biochemical and biophysical processes, and is also believed to be a key driver of macroevolutionary patterns. It is suggested that physiological constraints at low temperatures may diminish the fitness advantages of otherwise beneficial mutations; by contrast, relatively high, benign, temperatures allow beneficial mutations to efficiently show their phenotypic effects. To experimentally test this "mutational effects" mechanism, we examined the fitness effe ...[more]

PMID: 32424908

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Warmer temperatures enhance beneficial mutation effects.

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Warmer temperatures enhance beneficial mutation effects.

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