Next Article in Journal
Divergent Expression Patterns in Two Vernicia Species Revealed the Potential Role of the Hub Gene VmAP2/ERF036 in Resistance to Fusarium oxysporum in Vernicia montana
Previous Article in Journal
Development of Genetic Testing for Fragile X Syndrome and Associated Disorders, and Estimates of the Prevalence of FMR1 Expansion Mutations
Erratum published on 12 January 2017, see Genes 2017, 8(1), 29.
Open AccessArticle

Cucumber Metallothionein-Like 2 (CsMTL2) Exhibits Metal-Binding Properties

1
Key Laboratory of Horticulture Science for Southern Mountainous Regions, Ministry of Education, College of Horticulture and Landscape Architecture, Southwest University, No. 2 Tiansheng Road, Beibei, Chongqing 400715, China
2
Qijiang District Bureau of Forestry, Chongqing 401420, China
3
Institute of Vegetables and Flowers, Chongqing Academy of Agricultural Sciences, Chongqing 401329, China
*
Authors to whom correspondence should be addressed.
These authors contributed equally to this work.
Academic Editor: Paolo Cinelli
Genes 2016, 7(12), 106; https://doi.org/10.3390/genes7120106
Received: 21 August 2016 / Revised: 24 October 2016 / Accepted: 14 November 2016 / Published: 30 November 2016
(This article belongs to the Section Molecular Genetics and Genomics)
We identified a novel member of the metallothionein (MT) family, Cucumis sativus metallothionein-like 2 (CsMTL2), by screening a young cucumber fruit complementary DNA (cDNA) library. The CsMTL2 encodes a putative 77-amino acid Class II MT protein that contains two cysteine (Cys)-rich domains separated by a Cys-free spacer region. We found that CsMTL2 expression was regulated by metal stress and was specifically induced by Cd2+ treatment. We investigated the metal-binding characteristics of CsMTL2 and its possible role in the homeostasis and/or detoxification of metals by heterologous overexpression in Escherichia coli cells. Furthermore, we produced a deletion mutant form of the protein, CsMTL2m, that contained the two Cys-rich clusters but lacked the spacer region, in E. coli. We compared the metal-binding properties of CsMTL2 with those of CsMTL2m, the β domain of human metallothionein-like protein 1 (HsMTXb), and phytochelatin-like (PCL) heterologously expressed in E. coli using metal-binding assays. We found that E. coli cells expressing CsMTL2 accumulated the highest levels of Zn2+ and Cd2+ of the four transformed cell types, with levels being significantly higher than those of control cells containing empty vector. E. coli cells expressing CsMTL2 had a higher tolerance for cadmium than for zinc ions. These findings show that CsMTL2 improves metal tolerance when heterologously expressed in E. coli. Future studies should examine whether CsMTL2 improves metal tolerance in planta. View Full-Text
Keywords: cucumber; CsMTL2; metallothionein; metal-binding properties cucumber; CsMTL2; metallothionein; metal-binding properties
Show Figures

Figure 1

MDPI and ACS Style

Pan, Y.; Pan, Y.; Zhai, J.; Xiong, Y.; Li, J.; Du, X.; Su, C.; Zhang, X. Cucumber Metallothionein-Like 2 (CsMTL2) Exhibits Metal-Binding Properties. Genes 2016, 7, 106.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop