Abstract: The embryogenesis-associated protein EMB8 (DoEMB8) in Dendrobium officinale Kimura et Migo was achieved by RACE and nest PCR technologies. The full length of DoEMB8 was 2077 bp, contained an open reading frame (ORF) of 1824 bp that encoded 608 amino acid residues. Phylogenetic analysis showed that DoEMB8 had the closest relationship with Phoenix dactylifera, Elaeis guineensis, Musa acuminata subsp. malaccensis and some other monocotyledon. DoEMB8 had 2 transmembrane helix structures and probably existed in mitochondrion analyzed by TMHMM and TargetP, respectively. RT-qPCR analysis showed that the expression level of DoEMB8 was relatively constant in different development stages of protocorm, while it was higher in PLB(Protocorm like body) compared to that in protocorm. In different tissues, the expression level of DoEMB8 was highest in seed and was 3.16 times higher than that in root, indicating that DoEMB8 had relatively constant and higher expression level in embryonic development and may play an important role in plant embryonic development.

Key words: Dendrobium officinale Kimura et Migo, embryogenesis-associated protein EMB8, RACE, RT-qPCR