Cloning and expression analysis of a tyrosine decarboxylase gene from Rehmannia glutinosa

Abstract

Tyrosine decarboxylase (TyrDC) is an important enzyme in the secondary metabolism of several plant species, and was hypothesized to play a key role in the biosynthesis of phenylethanoid glycosides. Based on the transcriptome data, we cloned the full-length cDNA (GenBank accession NO. KU640395) of RgTyDC gene from Rehmannia glutinosa, and then performed bioinformatic analysis of the sequence. Further, we detected the expression pattern in different organs and hair roots treated with four elicitors by qRT-PCR. The results showed that the full length of RgTyDC cDNA was 1 530 bp encoding 509 amino acids. The molecular weight of the putative RgTyDC protein was about 56.6 kDa and the theoretical isoelectric point was 6.25. The RgTyDC indicated the highest homology with Sesamum indicum SiTyDC and Erythranthe guttata EgTyDC, both of them were reached 88%. RgTyDC highly expressed in R. glutinosa leaf, especially in senescing leaf, and rarely expressed in tuberous root. After the treatment of SA and MeJA, the relative expression level of RgTyDC mRNA was substantially increased. The results provide a foundation for exploring the molecular function of RgTyDC involved in phenylethanoid glycosides biosynthesis.