Expression of the hyp-1 gene in early stages of development of Hypericum perforatum L.

Abstract

Level of expression of the hyp-1 gene encoding for the phenolic coupling protein which is assumed to be involved in conversion of emodin to hypericin in vitro was compared in different organs of Hypericum perforatum seedlings in early stage of development in order to find out the sites of hypericin biosynthesis. Hypericins are accumulated in multicellular dark glands distributed on the aerial parts of H. perforatum, however, the site of the final stages of their biosynthesis remains unclear. In order to verify biosynthetic capacity of the dark glands, the level of expression of the hyp-1 gene in root, stem, shoot apex, intact leaf, leaf lamina free of and leaf margins containing dark glands performed by quantitative reverse transcription real-time PCR (qRT-PCR) was compared. The results did not reveal any significant difference in the level of hyp-1 expression in the analyzed leaf tissues. Surprisingly, the highest expression level was found in roots, which contain neither any dark glands nor more than just traces of hypericin. The lowest expression level was found in the plant stem and shoot apex. The results may either indicate that the final stages of hypericin biosynthesis take place in different plant parts, mainly in roots, which are not essentially associated with the dark glands and primarily serve for hypericin accumulation or rise a question on the coding function of the respective gene in situ.

Optimization of Protein Extraction from Hypericum perforatum Tissues and Immunoblotting Detection of Hyp-1 at Different Stages of Leaf Development

“…This is the first study of the presence of Hyp-1 protein in H. perforatum. The role of Hyp-1 in the biosynthesis of hypericins is not fully understood [11,21]. However, our results of the presence of Hyp-1 in H. perforatum leaves at different developmental stages are in agreement with the report of accumulation of hypericins in the plant.…”

Molecular cloning and tissue-specific expression of two cDNAs encoding polyketide synthases from Hypericum perforatum

“…and HpPKS2 genes with the contents of major bioactive compounds in different H. perforatum tissues Hypericins and pseudohypericins are shown to accumulate into multicellular dark glands found primarily on leaf margins and flowers of H. perforatum (Briskin and Gawienowski, 2001;Onelli et al, 2002;Zobayed et al, 2006;Košuth et al, 2007). The stems usually contain fewer dark glands, and glands cannot be found from the roots of H. perforatum (Košuth et al, 2007).…”

Spatial chemo-profiling of hypericin and related phytochemicals in Hypericum species using MALDI-HRMS imaging

“…More recently, however, it was revealed that the hyp-1 gene might not have a function in hypericin biosynthesis. We studied the expression of the hyp-1 gene in different organs of H. perforatum seedlings in early stages of development, which was believed to indicate the location of the sites of biosynthesis of hypericin [18]. We revealed that the sites of biogenesis and accumulation of hypericin in Hypericum plants were independent of the expression of the hyp-1 gene at the transcript level.…”