OBJECTIVE: To investigate differential
gene expression profiling of symbiotic germinated
seeds of
Dendrobium officinale.
METHODS: cDNAs from 5-week symbiotic germinated
seeds and 5-week aseptic cultivated
seeds , taken as the tester and driver respectively, were used to construct a suppressive
subtractive hybridization (SSH)
cDNA library .
RESULTS: By sequencing positive
clones and BLASTx
analysis against
GenBank database, 100
expressed sequence tags (EST) homologous to
plant known
genes were obtained. Functional annotation revealed that they were grouped into serials of cellular processes including
cell and
chromosome structure ,
RNA synthesis,
signal transduction ,
energy metabolism ,
protein synthesis and degradation, and
cell defense, etc. Real-
time quantitative RT-PCR analyses showed that the five randomly selected
genes were all up-regulated in symbiotic germinated
seeds .
CONCLUSION: The symbiotic
seed germination of D. officinale is involved in multiple pathways, and the results of this study
will lay a
foundation for further molecular elucidation of
seed germination in
Orchidaceae .