Research Articles

UV-B induced transcript accumulation of DAHP synthase in suspension-cultured Catharanthus roseus cells



The enzyme 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAHP) synthase (EC catalyzes the first committed step in the shikimate pathway of tryptophan synthesis, an important precursor for the production of terpenoid indole alkaloids (TIAs). A full-length cDNA encoding nuclear coded chloroplast-specific DAHP synthase transcript was isolated from a Catharanthus roseus cDNA library. This had high sequence similarity with other members of plant DAHP synthase family. This transcript accumulated in suspension cultured C. roseus cells on ultraviolet (UV-B) irradiation. Pretreatment of C.roseus cells with variety of agents such as suramin, N-acetyl cysteine, and inhibitors of calcium fluxes and protein kinases and MAP kinase prevented this effect of UV-B irriadiation. These data further show that the essential components of the signaling pathway involved in accumulation DAHP synthase transcript in C. roseus cells include suramin-sensitive cell surface receptor, staurosporine-sensitive protein kinase and MAP kinase.

  • Year: 2010
  • Volume: 5
  • Page/Article: Art. 13
  • DOI: 10.1186/1750-2187-5-13
  • Submitted on 4 Sep 2008
  • Accepted on 13 Aug 2010
  • Published on 13 Aug 2010