Cellular plasticity in response to suppression of storage proteins in the brassica napus embryo

authored by
Hardy Rolletschek, Jörg Schwender, Christina König, Kent D Chapman, Trevor Romsdahl, Christin Lorenz, Hans-Peter Braun, Peter Denolf, Katrien van Audenhove, Eberhard Munz, Nicolas Heinzel, Stefan Ortleb, Twan Rutten, Sean McCorkle, Taras Borysyuk, André Gündel, Hai Shi, Michiel Vander Auwermeulen, Stéphane Bourot, Ljudmilla Borisjuk
Abstract

The tradeoff between protein and oil storage in oilseed crops has been tested here in oilseed rape (Brassica napus) by analyzing the effect of suppressing key genes encoding protein storage products (napin and cruciferin). The phenotypic outcomes were assessed using NMR and mass spectrometry imaging, microscopy, transcriptomics, proteomics, metabolomics, lipidomics, immunological assays, and flux balance analysis. Surprisingly, the profile of storage products was only moderately changed in RNA interference transgenics. However, embryonic cells had undergone remarkable architectural rearrangements. The suppression of storage proteins led to the elaboration of membrane stacks enriched with oleosin (sixfold higher protein abundance) and novel endoplasmic reticulum morphology. Protein rebalancing and amino acid metabolism were focal points of the metabolic adjustments to maintain embryonic carbon/nitrogen homeostasis. Flux balance analysis indicated a rather minor additional demand for cofactors (ATP and NADPH). Thus, cellular plasticity in seeds protects against perturbations to its storage capabilities and, hence, contributes materially to homeostasis. This study provides mechanistic insights into the intriguing link between lipid and protein storage, which have implications for biotechnological strategies directed at improving oilseed crops.

Organisation(s)
Institute of Plant Genetics
External Organisation(s)
Brookhaven National Laboratory (BNL)
University of North Texas
BASF Innovation Center Ghent
Leibniz Institute of Plant Genetics and Crop Plant Research (IPK)
Denton ISD
Type
Article
Journal
The plant cell
Volume
32
Pages
2383-2401
No. of pages
19
ISSN
1040-4651
Publication date
30.04.2020
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Plant Science, Cell Biology
Electronic version(s)
https://doi.org/10.1105/tpc.19.00879 (Access: Closed)
https://doi.org/10.15488/11677 (Access: Open)