Microbiome Affects the Adaptation of Drosophila melanogaster to a High NaCl Concentration

Abstract

Symbiotic microbes affect many aspects of the life of multicellular organisms and may favor their adaptation to a changing environment, but there is little direct experimental evidence of such a contribution. To assess the possible role of the microbiome in the adaptation of Drosophila melanogaster to a high-NaCl feed substrate, we used two laboratory lines of salt-adapted flies (C1, C2) and two control lines cultivated on a standard feed without salt (H1, H2). We have already shown that the presowing of homogenate of flies C1 on the surface of a saline feed increases the breeding efficiency and enhances the development of drosophila larvae in comparison with a homogenate of H1 flies. We repeated this experiment for lines C2 and H2 and obtained similar data, which proves the reproducibility of the revealed effect. In addition, we found contrasting differences in the number and taxonomic composition of yeast in drosophila homogenates of the salt-adapted and control lines. The results correspond to the assumption that changes in the symbiotic microbiome, including its yeast component, may contribute to the adaptation of drosophila to unfavorable feed substrates. The possible evolutionary consequences of such a contribution are discussed in this work.