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)