Down‐regulation of key genes involved in carbon metabolism in Medicago truncatula results in increased lipid accumulation in vegetative tissue

A - Papers appearing in refereed journals

Wijekoon, C., Singer, S. D., Weselake, R. J., Petrie, J. R., Chen, G., Singh, S., Eastmond, P. J. and Acharya, S. N. 2020. Down‐regulation of key genes involved in carbon metabolism in Medicago truncatula results in increased lipid accumulation in vegetative tissue . Crop Science. 60 (4), pp. 1798-1808. https://doi.org/10.1002/csc2.20124

AuthorsWijekoon, C., Singer, S. D., Weselake, R. J., Petrie, J. R., Chen, G., Singh, S., Eastmond, P. J. and Acharya, S. N.
Abstract

Alfalfa (Medicago sativa L.), is the most widely grown perennial forage crop, which is a close relative of the model diploid legume Medicago truncatula. However, use of alfalfa lead to substantial greenhouse gas emissions and economic losses related to inefficiencies in rumen fermentation. The provision of supplemental lipids has been used as a strategy to mitigate these issues, but it is a costly approach. The ability to enhance lipid content within the vegetative tissues of alfalfa would therefore be very advantageous. As such, our aim was to assess and select gene candidates to increase total shoot lipid content in M. truncatula using a virus‐induced gene silencing (VIGS) approach. We targeted gene homologs of the SUGAR‐DEPENDANT 1 (SDP1), ADP‐GLUCOSE‐PYROPHOSPHORYLASE SMALL SUBUNIT 1 (APS1), TRIGALACTOSYLDIACYLGLYCEROL 5 (TGD5) and PEROXISOMAL ABC TRANSPORTER 1 (PXA1) in M. truncatula for silencing. Reduced target transcript levels were confirmed and changes of shoot lipid content and fatty acid composition were measured. Silencing of SDP1, APS1 and PXA1 each resulted in significant increases in shoot total lipid content. Significantly increased proportions of α‐linolenic acid (18:3Δ9cis,12cis,15cis) were observed and stearic acid (18:0) levels significantly decreased in the total acyl lipids extracted from vegetative tissues of each of the M. truncatula silenced plants. In contrast, palmitic acid (16:0) levels were significantly decreased in only SDP1 and PXA1‐silenced plants. Genes of PXA1 and SDP1 would be ideal targets for mutation as a means of improving the quality of alfalfa for increasing feed efficiency and minimizing greenhouse gas emissions from livestock production in the future.

KeywordsVirus-induced gene silencing; Feed quality; Forage legume; Lipid metabolism; Methane emissions; Downregulation
Year of Publication2020
JournalCrop Science
Journal citation60 (4), pp. 1798-1808
Digital Object Identifier (DOI)https://doi.org/10.1002/csc2.20124
Open accessPublished as green open access
FunderBiotechnology and Biological Sciences Research Council
Funder project or codeTailoring Plant Metabolism
Accepted author manuscript
Output statusPublished
Publication dates
Online12 Aug 2020
Publication process dates
Accepted11 Feb 2020
PublisherCrop Science Soc Amer
ISSN0011-183X

Permalink - https://repository.rothamsted.ac.uk/item/975vx/down-regulation-of-key-genes-involved-in-carbon-metabolism-in-medicago-truncatula-results-in-increased-lipid-accumulation-in-vegetative-tissue

Restricted files

Publisher's version

Under embargo indefinitely

63 total views
80 total downloads
4 views this month
1 downloads this month
Download files as zip