Tools for In Vitro Propagation/Synchronization of the Liverwort Marchantia polymorpha and Application of a Validated HPLC-ESI-MS-MS Method for Glutathione and Phytochelatin Analysis

Abstract

Bryophytes, due to their poikilohydric nature and peculiar traits, are useful and versatile organisms for studies on metal accumulation and detoxification in plants. Among bryophytes, the liverwort Marchantia polymorpha is an excellent candidate as a model organism, having a key role in plant evolutionary history. In particular, M. polymorpha axenic cultivation of gametophytes offers several advantages, such as fast growth, easy propagation and high efficiency of crossing. Thus, the main purpose of this work was to promote and validate experimental procedures useful in the establishment of a standardized set-up of M. polymorpha gametophytes, as well as to study cadmium detoxification processes in terms of thiol-peptide production, detection and characterisation by HPLC-mass spectrometry. The results show how variations in the composition of the Murashige and Skoog medium impact the growth rate or development of this liverwort, and what levels of glutathione and phytochelatins are produced by gametophytes to counteract cadmium stress.

Phytochelatins: Sulfur-Containing Metal(loid)-Chelating Ligands in Plants

“…In addition, the metal's effect may depend on the endogenous content of glutathione. Thus, the glutathione concentration in M. polymorpha gametophytes was constitutively low compared to higher plants, but a significant increase in its level was observed under the treatment with Cd [76,77].…”

“…Arachis hypogaea [70], P. sativum seedlings [72], in the roots of Pistia stratiotes [178], O. sativa [83,85], and Z. mays [88,179,180], and in suspension-cultured cells of Solanum lycopersicum [102], while an As-induced decrease in the concentration of glutathione was shown in the roots of S. atrocinerea [99] and O. sativa [84]. However, in the hyperaccumulators A. halleri, N. caerulescens, and S. alfredii [48,181], the accumulator P. frutescens [75], in the roots of Phragmites australis [87] and Cajanus cajan [182], in the roots and shoots of Solanum lycopersicum [108], and in the liverwort M. polymorpha [76,77], in the presence of Cd an opposite pattern was observed. The effect of Cd, as well as other metals, on the content of glutathione may differ depending on the plant organ, the duration of exposure, and the concentration of the metal in the medium [42], which may partly explain the conflicting results obtained for B. juncea [61,183,184] and A. thaliana [48,55].…”