Assessment of plants from the Brassicaceae family as genetic models for the study of nickel and zinc hyperaccumulation

Abstract

Summary• We report on the second phase of a programme to select a relative of Arabidopsis thaliana for use in large-scale molecular genetic studies of nickel (Ni) and zinc (Zn) hyperaccumulation. We also report on the relatedness among Thlaspi caerulescens accessions and the utility of using O -acetyl-L -serine as a marker for Ni and Zn hyperaccumulation potential.• Twenty-seven new accessions of metal-accumulating species collected in the Czech Republic, France, Greece, Italy, Slovenia and the USA during Spring-Summer 2002 were evaluated.• The criteria established for selection were hyperaccumulation of metals (Ni and Zn); compact growth habit; reasonable time to flowering; production of ≥ 1000 seeds per plant; self-fertility; compact diploid genome; high sequence similarity to A. thaliana ; ≥ 0.1% transformation efficiency with easy selection.• We conclude that the best candidate identified in the first phase was the best candidate overall: T. caerulescens accession St Félix de Pallières.

Chromosomal Phylogeny and Karyotype Evolution in x=7 Crucifer Species (Brassicaceae)

“…We analyzed three species of Lineage II (Glastaria glastifolia, Myagrum perfoliatum (Peer et al, 2006) and T. halophila is an important model of salt and cold tolerance (Gong et al, 2005).…”

Complexation and Toxicity of Copper in Higher Plants. II. Different Mechanisms for Copper versus Cadmium Detoxification in the Copper-Sensitive Cadmium/Zinc Hyperaccumulator Thlaspi caerulescens (Ganges Ecotype)

“…Plants developed a number of strategies to resist this toxicity, including active efflux, sequestration, and binding of heavy metals inside the cells by strong ligands. Among the zinc (Zn) and cadmium (Cd) hyperaccumulators (Brooks, 1998;Lombi et al, 2000), the best known species is Thlaspi caerulescens, which has been proposed as a hyperaccumulator model species by several authors (Assunção et al, 2003;Peer et al, 2003Peer et al, , 2006). An enhanced uptake of metals into the root symplasm was found in T. caerulescens compared with the related nonaccumulator Thlaspi arvense (Lasat et al, 1996(Lasat et al, , 1998, and a reduced sequestration into the root vacuoles was associated with the higher root-to-shoot translocation efficiency of T. caerulescens (Shen et al, 1997;Lasat et al, 1998).…”

An evolutionary and functional genomics study of Noccaea caerulescens, a heavy metal hyperaccumulating plant species

“…Flowering in N. caerulescens is dependent on vernalisation. When grown under greenhouse conditions, ecotypes cultivated thus far require up to 32 weeks to flower, including 7-12 weeks for vernalisation (5°C, and 12 h or 8 h photoperiod) to induce flowering in plants that are 2 months old, followed by an additional 4 weeks for seed ripening (Peer et al, 2003(Peer et al, , 2006Lochlainn et al, 2011;Guimarães et al, 2013). The life history of N. caerulescens varies among ecotypes and appears to be intermediate between the annual plant A. thaliana and the perennial plant Arabis.…”

“…N. caerulescens is an extremophile, adapted to grow on soil with high concentrations of Ni, Zn, Pb or Cd. Next to displaying extreme heavy metal tolerance, it is also a heavy metal hyperaccumulator, with genotypes able to accumulate Ni, Zn and Cd to over 1% of their dry weight in shoots (Assunção et al, 2003;Nascimento and Xing, 2006;Broadley et al, 2007;Krämer, 2010)Together with the Zn/Cd hyperaccumulator species Arabidopsis halleri, N. caerulescens is among the most prominent plant model systems to study heavy metal hyperaccumulation and associated hypertolerance (Krämer, 2010;Hanikenne and Nouet, 2011;Pollard et al, 2014), however, molecular genetic studies are challenging in this species because of its biennial life cycle of 7-9 months, including a 2-3 months vernalisation period to induce flowering (Peer et al, 2003(Peer et al, , 2006. This disadvantage limits the efficiency of genetic studies and breeding efforts to enhance its application in metal phytoremediation.…”

“…caerulescens is a biennial or facultative perennial plant from the same Brassicaceae family as A. thaliana and it has an obligate vernalisation requirement. When grown under greenhouse conditions, the accessions cultivated thus far require up to 32 weeks to flower, including a 7-12 week period of short-day vernalisation (5°C and 12 h or 8 h photoperiod) for young plants (2 months old) to induce flowering, with an additional 4 weeks for seed ripening, and a few extra weeks of dry storage to break seed dormancy (Assunção et al, 2003c;Peer et al, 2003Peer et al, , 2006Lochlainn et al, 2011;Guimarães et al, 2013). These limitations, particularly the requirement for greenhouse space to achieve vernalisation during the winter, mean that only one generation per year can be produced when developing the TILLING population.…”