# Exploring the molecular landscape of environmental responses in the Antarctic plant Colobanthus quitensis: insights from metatranscriptomic analysis

## TL;DR

This study explores how environmental conditions and microbes affect the Antarctic plant Colobanthus quitensis using transcriptomic and biochemical analyses.

## Contribution

The novel contribution is the integration of metatranscriptomic and biochemical data to reveal plant-microbe interactions under varying environmental conditions in Antarctica.

## Key findings

- Site 2 (Puchalski Station) provides optimal conditions for C. quitensis, enhancing physiological performance and stress responses.
- Microbial community composition varies significantly across sites, indicating environmental influence on plant-associated microbiota.
- Environmental changes are reflected in plant transcriptomic and biochemical responses, suggesting a potential early-warning system via the microbiome.

## Abstract

The harsh environmental conditions of Antarctica significantly influence plant responses, impacting both defence mechanisms and developmental processes. Moreover, plant-associated microbial communities further modulate physiological functions, creating a complex network of interactions. This study aimed to investigate how local environmental conditions and plant-associated microbiota shape the transcriptomic landscape of the Antarctic plant Colobanthus quitensis.

A comparative metatranscriptomic analysis was conducted on plants collected from three sites spanning a coastal-to-inland gradient of increasing climatic severity to investigate both the functional roles of differentially expressed plant genes and taxonomic profiling of the associated microbial community. In addition, the content of photosynthetic and protective pigments was quantified biochemically to assess whether environmental conditions influence the photosynthetic pathway.

The results suggested that Site 2 (Puchalski Station) represents a particularly favourable microenvironment that optimises the physiological performance of C. quitensis, supporting enhanced homeostasis and the activation of multiple stress-response strategies. Furthermore, distinct variations in microbial community composition were observed across the sites, underscoring the interplay between local environment and plant-associated microbiota.

These findings highlight the sensitivity of C. quitensis to minor environmental changes and suggest that its associated microbiome could serve as an early-warning system for ecological change in Antarctica.