title: Gene expression differences between Noccaea caerulescens ecotypes help to identify candidate genes for metal phytoremediation.
abstract: Populations of Noccaea caerulescens show tremendous differences in their capacity to hyperaccumulate and hypertolerate metals. To explore the differences that could contribute to these traits, we undertook SOLiD high-throughput sequencing of the root transcriptomes of three phenotypically well-characterized N. caerulescens accessions, i.e., Ganges, La Calamine, and Monte Prinzera. Genes with possible contribution to zinc, cadmium, and nickel hyperaccumulation and hypertolerance were predicted. The most significant differences between the accessions were related to metal ion (di-, trivalent inorganic cation) transmembrane transporter activity, iron and calcium ion binding, (inorganic) anion transmembrane transporter activity, and antioxidant activity. Analysis of correlation between the expression profile of each gene and the metal-related characteristics of the accessions disclosed both previously characterized (HMA4, HMA3) and new candidate genes (e.g., for nickel IRT1, ZIP10, and PDF2.3) as possible contributors to the hyperaccumulation/tolerance phenotype. A number of unknown Noccaea-specific transcripts also showed correlation with Zn(2+), Cd(2+), or Ni(2+) hyperaccumulation/tolerance. This study shows that N. caerulescens populations have evolved great diversity in the expression of metal-related genes, facilitating adaptation to various metalliferous soils. The information will be helpful in the development of improved plants for metal phytoremediation.
authors.affiliation: Department of Biology, University of Eastern Finland , P.O. Box 1627, Kuopio, 70210, Finland.
authors.forename: Pauliina
authors.initials: P
authors.lastname: Halimaa
authors.forename: Ya-Fen
authors.initials: YF
authors.lastname: Lin
authors.forename: Viivi H
authors.initials: VH
authors.lastname: Ahonen
authors.forename: Daniel
authors.initials: D
authors.lastname: Blande
authors.forename: Stephan
authors.initials: S
authors.lastname: Clemens
authors.forename: Attila
authors.initials: A
authors.lastname: Gyenesei
authors.forename: Elina
authors.initials: E
authors.lastname: Häikiö
authors.forename: Sirpa O
authors.initials: SO
authors.lastname: Kärenlampi
authors.forename: Asta
authors.initials: A
authors.lastname: Laiho
authors.forename: Mark G M
authors.initials: MG
authors.lastname: Aarts
authors.forename: Juha-Pekka
authors.initials: JP
authors.lastname: Pursiheimo
authors.forename: Henk
authors.initials: H
authors.lastname: Schat
authors.forename: Holger
authors.initials: H
authors.lastname: Schmidt
authors.forename: Marjo H
authors.initials: MH
authors.lastname: Tuomainen
authors.forename: Arja I
authors.initials: AI
authors.lastname: Tervahauta
mesh_terms: D001673:Biodegradation, Environmental; D019607:Brassicaceae / Q000235:genetics* / Q000378:metabolism*; D060146:Ecotype; D020869:Gene Expression Profiling; D019216:Metals, Heavy / Q000378:metabolism*; D010940:Plant Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D012989:Soil Pollutants / Q000378:metabolism; D059467:Transcriptome / Q000235:genetics*
chemical_list: D019216:Metals, Heavy; D010940:Plant Proteins; D012989:Soil Pollutants