Abstract:Rehmannia glutinosa was used as experimental material in this study. Through analyzing the transcriptome data of R. glutinosa and designing specific primers, we isolated the cDNA sequence of geranylgeranyl pyrophosphate synthase (GGPPS) from R. glutinosa and named as RgGGPPS1 (GenBank accession No. KU258808). Meanwhile, on the basis of bioinformatic analysis, we performed the prokaryotic expression, purification and tissuespecific expression analysis. The results indicated that: (1) RgGGPPS1 has an open reading frame (ORF) of 987 bp, which encoded a protein of 328 amino acid residues. (2) Bioinformatic analysis indicated that RgGGPPS1 protein contains the two conserved motifs (DDXXXXDD) and (DDXXD); RgGGPPS1 protein showed the highest homology, 92% identity, with GGPPS protein from Sesamum indicum. (3) By utilizing the construction of prokaryotic expression vector pET32aRgGGPPS1, we successfully expressed the recombinant RgGGPPS1 protein in E. coli BL21 (DE3) cells. Furthermore, the recombinant RgGGPPS1 protein was purified through Ni2+ affinity chromatography. (4) Realtime PCR analysis indicated that RgGGPPS1 was expressed in high transcript level in roots, low levels in leaves and stems. The results of this study provided the fundamental information about RgGGPPS1 gene for followup research of its function involved in iridoid glycoside biosynthesis pathway.