Abstract: The full-length cDNA sequences of F3’H gene（designated as GbF3’H）were isolated from Ginkgo biloba for the first time，GenBank No. KP056747. The full-length cDNA of GbF3’H is 2 144 bp long and contains a 1 671 bp open reading frame（ORF）encoding a 556 amino acid protein，with a predicted molecular weight of about 63.47 kD and an isoelectric point of 7.71. Phylogenetic tree analysis revealed that GbF3’H shared the same ancestor with other F3’H，but the divergence time is early. Bioinformatics analysis show that GbF3’H have a signal recognition peptide and belong to a microsomal cytochrome P450-dependent monooxygenases multigene families. The expression analysis by RT-PCR showed that GbF3’H had tissue specific manner in G. biloba，and the highest expression in stamens，thenext in mature leaves and gynoecium which were great difference with other flavones biosynthetic pathway gene. GbF3’H transcription level was also found to be significant up-regulated by 6-BA，SA，ABA，IAA，but wound treatment had no significant change. It’s also found that the GbF3’H promoter sequence contain the regulation cis-acting element assist with flavonoids biosynthesis. The result suggested that the expression model of GbF3’H gene has close relation with the formation of flavonoids and anthocyanin biosynthesis，which indicated that the F3’H regulate the flavonoids transfering to anthocyanin in G. biloba.

Key words: Ginkgo biloba, flavonoid 3’-hydroxylase, flavonoids, transcript regulation