About this Journal Submit a Manuscript Table of Contents
BioMed Research International
Volume 2013 (2013), Article ID 904769, 12 pages
http://dx.doi.org/10.1155/2013/904769
Research Article

ScMT2-1-3, a Metallothionein Gene of Sugarcane, Plays an Important Role in the Regulation of Heavy Metal Tolerance/Accumulation

Key Lab of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China

Received 10 February 2013; Revised 3 May 2013; Accepted 8 May 2013

Academic Editor: Sudhir Sopory

Copyright © 2013 Jinlong Guo et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Plant metallothioneins (MTs), which are cysteine-rich, low-molecular-weight, and metal-binding proteins, play important roles in detoxification, metal ion homeostasis, and metal transport adjustment. In this study, a novel metallothionein gene, designated as ScMT2-1-3 (GenBank Accession number JQ627644), was identified from sugarcane. ScMT2-1-3 was 700 bp long, including a 240 bp open reading frame (ORF) encoding 79 amino acid residues. A His-tagged ScMT2-1-3 protein was successfully expressed in Escherichia coli system which had increased the host cell’s tolerance to Cd2+, Cu2+, PEG, and NaCl. The expression of ScMT2-1-3 was upregulated under Cu2+ stress but downregulated under Cd2+ stress. Real-time qPCR demonstrated that the expression levels of ScMT2-1-3 in bud and root were over 14 times higher than those in stem and leaf, respectively. Thus, both the E. coli assay and sugarcane plantlets assay suggested that ScMT2-1-3 is significantly involved in the copper detoxification and storage in the cell, but its functional mechanism in cadmium detoxification and storage in sugarcane cells needs more testification though its expressed protein could obviously increase the host E. coli cell’s tolerance to Cd2+. ScMT2-1-3 constitutes thus a new interesting candidate for elucidating the molecular mechanisms of MTs-implied plant heavy metal tolerance/accumulation and for developing sugarcane phytoremediator varieties.