Linking Ecological, Environmental and Biogeochemical Data with Multi'omics Analysis

Harald Hasler-Sheetal1, Max CN Castorani2, Lena Fragner3, Yonghui Zeng1, Marianne Holmer4, Ronnie N Glud1, Wolfram Weckwerth3 and Donald E Canfield1, (1)University of Southern Denmark, Nordic Center of Earth Evolution, Department of Biology, Odense, Denmark, (2)University of California, Marine Science Institute, Santa Barbara, CA, United States, (3)University of Vienna, MOSYS, Vienna, Austria, (4)University of Southern Denmark, Biology, Odense, Denmark
Abstract:
The integrated analysis of multi’omics and environmental data provides a holistic understanding of biological processes and has been proven to be challenging. Here we present our research concept for conducting multi-omics experiments and linking them to environmental data.

Hypoxia, reduced light availability and species interaction – all amplified by global warming – cause a global decline of seagrasses. Metabolic mechanisms for coping with these global threats are largely unknown and multi’omics approaches can be an important approach for generating this insight.

We applied GC, LC-qTOF-MS and bioinformatics to investigate the effects of environmental pressure on metabolites present in seagrasses.

In a first experiment we assessed the metabolomics response of the seagrass Zostera marina towards anoxia and showed that photosynthetically derived oxygen could satisfy the oxygen demand in the leaves. But accumulation of fermentation products in the roots showed that the rhizosphere was under anoxic stress. In contrast nocturnal anoxia caused a biphasic shift in the metabolome of roots and leaves. This nocturnal reprogramming of the metabolome under anoxia indicates a mitigation mechanism to avoid the toxic effects. A pathway enrichment analysis proposes the alanine shunt, the GABA shunt and the 2-oxoglutarate shunt as such mitigation mechanisms that alleviate pyruvate levels and lead to carbon and nitrogen storage during anoxia.

In a second experiment, varying light exposure and species interaction of Z. marina with the blue mussel Mytilus edulis – a co-occurring species in seagrass systems – resulted in treatment specific metabolic fingerprints in seagrass. Light modified the metabolic fingerprint expressed in Z. marina to the presence of mussels, indicating varying physiological responses to mussels in normal and low light regimes. Multivariate data-analysis indicated light exposure as main driver (45%) and mussel presence as minor driver (13%) for the metabolic responses. Traditional plant performance parameters exhibited light dependent variation but in contrast to the metabolome none of these parameters were dependent on the presence of M. edulis. This demonstrates the applicability of metabolomics to reveal hidden effects of environmental pressure on seagrasses.

Back to: Proteomics and Lipidomics: Expanding the Macromolecular Toolbox to Understand Oceanic Processes