4.8 Article

Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometry Imaging of Metabolites during Sorghum Germination1[OPEN]

Journal

PLANT PHYSIOLOGY
Volume 183, Issue 3, Pages 925-942

Publisher

AMER SOC PLANT BIOLOGISTS
DOI: 10.1104/pp.19.01357

Keywords

-

Categories

Funding

  1. VELUX Foundation [VKR023054, 19151]
  2. European Research Council (ERC) [323034]
  3. Danish National Research Foundation (Danmarks Grundforskningsfond) [DNRF99]
  4. Centre of Excellence for Environmental Decisions, Australian Research Council [LP0774941, LP100100434, DP130101049]
  5. Det Frie Forskningsrad (Danish Council for Independent Research) [DFF-4002-00391]
  6. Det Frie Forskningsrad (Pacific Seeds Pty Ltd)
  7. Carlsberg Foundation forMALDI-MSI instrumentation
  8. Department of Industry, Innovation, Science, Research and Tertiary Education, Australian Government
  9. Australian Research Council [LP0774941, LP100100434] Funding Source: Australian Research Council

Ask authors/readers for more resources

Matrix-assisted laser desorption/ionization-mass spectrometry imaging reveals that biosynthesis and recycling of the plant defense compound dhurrin are key events during sorghum grain germination. Dhurrin is the most abundant cyanogenic glucoside found in sorghum (Sorghum bicolor)where it plays a key role in chemical defense by releasing toxic hydrogen cyanide upon tissue disruption. Besides this well-established function, there is strong evidence that dhurrin plays additional roles, e.g. as a transport and storage form of nitrogen, released via endogenous recycling pathways. However, knowledge about how, when and why dhurrin is endogenously metabolized is limited. We combined targeted metabolite profiling with matrix-assisted laser desorption/ionization-mass spectrometry imaging to investigate accumulation of dhurrin, its recycling products and key general metabolites in four different sorghum lines during 72 h of grain imbibition, germination and early seedling development, as well as the spatial distribution of these metabolites in two of the lines. Little or no dhurrin or recycling products were present in the dry grain, but their de novo biosynthesis started immediately after water uptake. Dhurrin accumulation increased rapidly within the first 24 h in parallel with an increase in free amino acids, a key event in seed germination. The trajectories and final concentrations of dhurrin, the recycling products and free amino acids reached within the experimental period were dependent on genotype. Matrix-assisted laser desorption/ionization-mass spectrometry imaging demonstrated that dhurrin primarily accumulated in the germinating embryo, confirming its function in protecting the emerging tissue against herbivory. The dhurrin recycling products, however, were mainly located in the scutellum and/or pericarp/seed coat region, suggesting unknown key functions in germination.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.8
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available