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The oleaginous
Jatropha curcas
has been proposed as a promising source for biodiesel production in seed or potentially by
in vitro
production in cell cultures. However, little is known concerning the optimal growth conditions and the transcription of key factors and enzymes involved in the biosynthesis of storage lipids in
J. curcas
cell cultures. Additional knowledge is also needed for these factors in seeds. Here, we assess target gene expression in endosperm cells
in planta
and endosperm-derived cell suspension cultures (EDCCs). Endosperm cells were taken from three representative seed developmental stages, and cell suspensions were grown from these samples. Glucose, nitrogen, and abscisic acid concentrations were varied in an attempt to optimize biomass growth and oil yield. Oil production in EDCCs reached a maximum of 5% (w/w) of total lipids. Although much lower than lipid production in seed, lipid profiles of EDCCs remain identical to those produced
in planta
. The expression levels of five major transcription factors (TFs), as well as
KAS1
,
accA
,
DGAT1/2
and
PDAT1
enzymes, and the O
LE1
protein, all key components of the lipid biosynthesis pathway were also measured. Significant expression of
LEC1
,
FUS3
,
ABI3
, and
WRI1
was found in endosperm cells throughout seed development, suggesting similar functions to their counterparts in
Arabidopsis
and providing a reference expression level for cell cultures.
J. curcas
EDCCs showed lower expression of most TFs compared with endosperm tissue, with the exception of
WRI1
which had comparable expression levels in the two systems. Conversely, the enzymes
KAS1
,
accA
, and
DGAT
had the same or higher expression levels in EDCCs
versus
endosperm cells. Interestingly, the genes that encoded for
DGAT1
and
DGAT2
enzymes were found preferentially expressed in endosperm cells and EDCCs, respectively. Contrary to other studies, our findings indicate that the addition of ABA does not result in increased expression of genes involved in storage lipid biosynthesis.