The monthly transcriptome dynamics of Antarctic moss, Sanionia uncinata (Hedw.) Loeske, throughout the year in natural environments, reveals seasonal adaptation of extremophile plants

Abstract

Most organisms on Earth have evolved and adapted to the seasonally changing environment. The maritime Antarctic is covered with snow and ice for most of the year, but during the austral summer season, snow melts and a variety of vegetation is revealed. During this three-month period, terrestrial plants actively perform cellular activities under the prolonged daytimes. But even this short summer, the sub-zero temperatures, dryness, continuous strong light and UV radiation are very extreme conditions for plant growth, and after these summers are over, the snow starts to pile up and the plants stop growing and enter dormancy in a long and dark winter. Here, in this study, we investigated the annual transcriptome response of extremophile plants in a natural environment. During the 2015-2016 winter/summer station study, we had sampled Sanionia uncinata, one of the dominant bryophyte species of the maritime Antarctic, naturally habituated in the King George Island (62°14′ S; 58°44′ W), on a monthly basis, and conducted transcriptome analysis. As a result, we could identify groups of genes that fluctuate with rhythmicity according to the seasonal changes. The weighted co-expressed gene network analysis enabled to construct a correlation network on climate-gene expression and to identify the groups of genes responding to changing climatic factors in a natural environment.