Abstract
Cottonseed oil is recognized as an important oil in food industry
for its unique characters: low flavor reversion and the high level of
antioxidants (VitaminE) as well as unsaturated fatty acid. However, the
cottonseed oil content of cultivated cotton (Gossypium hirsutum) is only
around 20%. In this study, we modified the accumulation of oils by the
down-regulation of phosphoenolpyruvate carboxylase 1 (GhPEPC1) via RNA
interference in transgenic cotton plants. The qRT-PCR and enzyme activity assay
revealed that the transcription and expression of GhPEPC1was dramatically
down-regulated in transgenic lines. Consequently, the cottonseed oil content in
several transgenic lines showed a significant (P < 0.01) increase (up to
16.7%) without obvious phenotypic changes under filed condition when compared
to the control plants. In order to elucidate the molecular mechanism ofGhPEPC1 in the regulation of seed oil content, we
quantified the expression of the carbon metabolism related genes of
transgenic GhPEPC1 RNAi
lines by transcriptome analysis. This analysis revealed the decrease of GhPEPC1expression
led to the increase expression of triacylglycerol biosynthesis-related genes,
which eventually contributed to the lipid biosynthesis in cotton. This result
provides a valuable information for cottonseed oil biosynthesis pathway and
shows the potential of creating high cottonseed oil germplasm by RNAi strategy
for cotton breeding.
PMID: 27620452（IF=5.228）
DOI: 10.1038/srep33342