Chlorogenic acid participates in the regulation of shoot, root and root hair development in Hypericum perforatum

• Published in: Plant physiology and biochemistry 2011-08, Vol.49 (8), p.835-842
• Main Authors: Franklin, G., Dias, A.C.P.
• Format: Article
• Language: English
• Subjects: Aminoindane-2-phosphonic acid; Biological and medical sciences; Chlorogenic acid; Chlorogenic Acid - metabolism; Chlorogenic Acid - pharmacology; Dose-Response Relationship, Drug; Enzyme Inhibitors - pharmacology; Fundamental and applied biological sciences. Psychology; High performance liquid chromatography; Hypericum - drug effects; Hypericum - growth & development; Hypericum - metabolism; Hypericum perforatum; Indans; Indoleacetic Acids - pharmacology; Naphthaleneacetic Acids - pharmacology; Organogenesis; Organophosphonates - pharmacology; Phenylalanine Ammonia-Lyase - antagonists & inhibitors; Plant physiology and development; Plant Roots - drug effects; Plant Roots - growth & development; Plant Roots - metabolism; Plant Shoots - drug effects; Plant Shoots - growth & development; Plant Shoots - metabolism; Thin cell layer explant; Tissue Culture Techniques
• ISSN: 0981-9428; 1873-2690
• DOI: 10.1016/j.plaphy.2011.05.009

Chlorogenic acid (CGA), a product of the phenylpropanoid pathway, is one of the most widespread soluble phenolic compounds in the plant kingdom. Although CGA is known to have important roles in plant function, its relevance in plant de novo organogenesis is not yet understood. With a series of experiments, here we show that CGA has a potential role in shoot, root and root hair development. In the first phase of our investigation, we developed an efficient and novel thin cell layer (TCL) regeneration protocol for Hypericum perforatum which could bridge all the in vitro morphogenetic stages between single cell and complete plant. Tissues at different morphogenetic states were analysed for their phenolic profile which revealed that shoot differentiation from callus tissues of H. perforatum is accompanied by the onset of CGA production. Further, the relevance of CGA in de novo organogenesis was deciphered by culturing highly organogenic root explants on media augmented with various concentrations of CGA. Results of this experiment showed that CGA concentrations lower than 10.0 mg l −1 did not affect shoot organogenesis, whereas, higher concentrations significantly reduced this process in a concentration-dependent manner. In spite of the differential concentration-dependent effects of CGA on shoot regeneration, supplementation of CGA did not have any effect on the production of lateral roots and root hairs. Interestingly, CGA showed a concentration-dependent positive correlation with lateral roots and root hairs production in the presence of α-naphthaleneacetic acid (NAA). When the culture medium was augmented with 2-aminoindane-2-phosphonic acid (AIP), an inhibitor of phenylalanine ammonia lyase (PAL), induction of shoots, lateral roots and root hairs from the explants was significantly affected. Addition of an optimum concentration of CGA in these cultures partially restored all these organogenic processes. ► An efficient thin cell layer regeneration system for Hypericum perforatum is reported for the first time. ► Analysis of phenolic profile of tissues representing different morphogenetic states revealed the association of chlorogenic acid in shoot organogenesis. ► Feeding and inhibition studies revealed that an optimum chlorogenic acid level is necessary for proper development of shoots, roots and root hairs.