Background:
Jatropha curcas
L. (further referred to as
Jatropha), as a rapidly emerging biofuel crop, has attracted
worldwide interest. However,
Jatropha is still an undomesticated plant, the true potential of this shrub has not yet
been fully realized. To explore the potential of
Jatropha, breeding and domestication are needed. Seed size is one
of themost important traits of seed yield and has been selected since the beginning of agriculture. Increasing the
seed size is amain goal of
Jatropha domestication for increasing the seed yield, but the genetic regulation of seed
size in
Jatropha has not been fully understood.
Results:
We cloned
CYP78A98 gene from
Jatropha, a homologue of CYP78A5 in
Arabidopsis. We found that
CYP78A98 was highly expressed in male flower, female flower, stem apex, leaf and developing seed. However,
its transcripts were hardly detected in root and stem.
CYP78A98 protein localized in endoplasmic reticulum
(ER) and the hydrophobic domain at the N-terminus was essential for the correct protein localization.
Furthermore, INNER NO OUTER promoter (pINO) drove specific overexpression of
CYP78A98 in transgenic
tobacco seeds resulted in increased seed size andweight, aswell as improved seed protein and fatty acid content.
Conclusions:
The results indicated that
CYP78A98 played a role in
Jatropha seed size control. This may help us to
better understand the genetic regulation of
Jatropha seed development, and accelerate the breeding progress of
Jatropha.