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bioRxiv · 10.1101/2021.01.15.426840

Spatial metabolomics using imaging mass spectrometry to identify the localization of asparaptine in Asparagus officinalis

Nakabayashi, R.·Hashimoto, K.·Mori, T.·Toyooka, K.·Sudo, H.·Saito, K.
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Abstract

Spatial metabolomics uses imaging mass spectrometry (IMS) to localize metabolites within tissue section. Here, we performed matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance-IMS (MALDI-FTICR-IMS) to identify the localization of asparaptine, a naturally occurring inhibitor of angiotensin-converting enzyme, in green spears of asparagus (Asparagus officinalis). Spatial metabolome data were acquired with an untargeted manner. Segmentation analysis using the data characterized tissue-type-dependent and - independent distribution patterns in cross-sections of asparagus spears. Moreover, asparaptine accumulated at high levels in developing lateral shoot tissues. Quantification of asparaptine in lateral shoots using liquid chromatography-tandem mass spectrometry (LC-MS/MS) validated the IMS analysis. These results provide valuable information for understanding the function of asparaptine in asparagus, and identify the lateral shoot as a potential region of interest for multiomic studies to examine gene-to-metabolite associations in asparaptine biosynthesis.

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Nakabayashi, R., Hashimoto, K., Mori, T., Toyooka, K., Sudo, H., Saito, K.. 2021-01-17. Spatial metabolomics using imaging mass spectrometry to identify the localization of asparaptine in Asparagus officinalis. https://doi.org/10.1101/2021.01.15.426840

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