High-resolution magic angle spinning NMR studies for metabolic characterization of Arabidopsis thaliana mutants with enhanced growth characteristics

Abstract

Developing smart crops which yield more biomass to meet the increasing demand for plant biomass has been an active area of research in last few decades. We investigated metabolic alterations in two Arabidopsis thaliana mutants with enhanced growth characteristics that were previously obtained from a collection of plant lines expressing artificial transcription factors. The metabolic profiles were obtained directly from intact Arabidopsis leaves using high-resolution magic angle spinning (HR-MAS) NMR. Multivariate analysis showed significant alteration of metabolite levels between the mutants and the wild-type Col-0. Interestingly, most of the metabolites that were reduced in the faster-growing mutants are generally involved in the defence against stress. These results suggest a growth-defence trade-off in the phenotypically engineered mutants. Our results further corroborate the idea that plant growth can be enhanced by suppressing defence pathways.

A robust circadian rhythm of metabolites in Arabidopsis thaliana mutants with enhanced growth characteristics

“…In our earlier metabolomics study of the VP16-02-003 and VP16-05-014, eighteen biomarkers were identified at t = 6 hours after the start of the light period [8]. In the present study, the rhythm of these biomarkers is followed during the circadian cycle.…”

“…The metabolic profiles for every time-point obtained by 1 H HR-MAS NMR were investigated by multivariate analysis of the bucket-reduced 1 H NMR data, as has been described in our earlier work [8]. In Fig 4, orthogonal partial least square discriminant analysis (OPLS-DA) was carried out to examine the variation in metabolic profile between two mutants and the wild-type Col-0 throughout the light/dark cycle.…”

“…Arabidopsis thaliana accession Columbia-0 and VP16-02-003 and VP16-05-014 plants were grown as described previously [8], with slight modifications. Plants were grown in a climate-controlled growth cabinet (Bronson climate BV) instead of green house used in earlier study [8]. Use of growth cabinet was necessary to achieve controlled harvesting of the leaves at various time points during light/dark cycle.…”

“…Recently, we have also introduced a systems biology approach to resolve primary processes of metabolic regulation and conversion leading to enhanced growth from the complicated biological background, using non-invasive HR-MAS NMR [7]. In the previous work, the metabolic profile for both mutants was studied at one time-point in the middle of the light period of 12 hours in a 24-hour light/dark regime [8]. The changes in the metabolomics and transcriptomics of both mutants compared to the wild-type Arabidopsis thaliana accession Columbia-0 (Col-0) gave us insight into the improved growth characteristics of the mutants which were found to be a consequence of the reduce defence response in the context of the growth-defence trade-off [5,8–11].…”

NMR spectroscopy analysis reveals differential metabolic responses in arabidopsis roots and leaves treated with a cytokinesis inhibitor

“…The significance of arabidopsis as a model system has led to several nuclear magnetic resonance (NMR)-based metabolomics studies with both solution and solid-state samples [14][15][16][17]. Recently developed approaches of 1 H high-resolution magic angle spinning NMR, which are circumventing the need for elaborate sample preparation and allowing utilization of solidstate NMR spectroscopy, were employed for the study of intact arabidopsis leaves [18,19]. NMR-based methods for studying plant metabolomics, including sample preparation protocols and data analysis approaches, are being refined continuously [20,21], contributing to a proliferation in their utilization.…”