Desiccation tolerance in the Antarctic moss Sanionia uncinata

Abstract

Background One of the most extreme environments on our planet is the Maritime Antarctic territory, due to its low-water availability, which restricts the development of plants. Sanionia uncinata Hedw. (Amblystegiaceae), the main colonizer of the Maritime Antarctic, has effective mechanisms to tolerate this environment. It has been described that the tolerance to desiccation is mediated by the hormone abscisic acid (ABA), antioxidants systems, accumulation of compatible solutes and proteins of the late embryogenesis abundant (LEA). However, to date, these mechanisms have not been described in S. uncinata . Therefore, in this work, we postulate that the tolerance to desiccation in the Antarctic moss S. uncinata is mediated by the accumulation of ABA, the osmolytes proline and glycine betaine, and dehydrins (an LEA class 11 proteins). To demonstrate our hypothesis, S. uncinata was subjected to desiccation for 24 h (loss in 95% of water content), and the effects on its physiological, photosynthetic, antioxidant and biochemical parameters were determined. Results Our results showed an accumulation of ABA in response to water loss, and the activation of protective responses that involves an increment in levels of proline and glycine betaine, an increment in the activity of antioxidant enzymes such as SOD, CAT, APX and POD, and the accumulation of dehydrins proteins. Conclusion The results showed, suggest that S. uncinata is a desiccation-tolerant moss, property mediated by high cellular plasticity regulated by ABA.

Resistance of Antarctic moss Sanionia uncinata to photoinhibition: chlorophyll fluorescence analysis of samples from the western and eastern coasts of the Antarctic Peninsula

“…Sanionia uncinata can tolerate severe dehydration (Pizarro et al . 2019), and, thanks to the content of UV‐screening compounds and specific secondary metabolites (Newsham et al . 2002; Fernandes et al .…”

“…2016), desiccation (Pizarro et al . 2019) and freezing (Cannone et al . 2017).…”

The genomic and transcriptomic foundations of viviparous seed development in mangroves

“…Oleosin family proteins (orthogroups: OG0002151 and OG0007120) are another nutrient in seeds (Lu et al 2018) while seed maturation proteins (orthogroup: OG0014483 and OG0015329) are involved in secondary dormancy (Kushwaha et al 2012). Late embryogenesis abundant proteins (LEA) (orthogroup: OG0009552, OG0012500 and OG0012688) play an important role in the desiccation tolerance of plant seeds (Pizarro et al 2019). Thus, there are clear differences within these sets of proteins in terms of their coding genes and expressions between viviparous mangroves and orthodox seeds.…”

Efficient Heat Dissipation and Cyclic Electron Flow Confer Daily Air Exposure Tolerance in the Intertidal Seagrass Halophila beccarii Asch

“…Lower carbon assimilation upon air exposure with smaller seagrass leaves might also cause non-change of total carbon content. Furthermore, free amino acid accumulation, such as proline, is needed to adjust osmotic pressure to enhance tolerance to desiccation (Pandey et al, 2010;Pizarro et al, 2019), which might explain the increased nitrogen accumulation.…”