Limits...
Lead tolerance and accumulation in Hirschfeldia incana, a Mediterranean Brassicaceae from metalliferous mine spoils.

Auguy F, Fahr M, Moulin P, Brugel A, Laplaze L, Mzibri ME, Filali-Maltouf A, Doumas P, Smouni A - PLoS ONE (2013)

Bottom Line: The functional characterization of HiHMA4 and HiMT2a was achieved using Arabidopsis T-DNA insertional mutants.Pb content and primary root growth analysis confirmed the role of these two genes in Pb tolerance and accumulation.H. incana could be considered as a good experimental model to identify genes involved in lead tolerance and accumulation in plants.

View Article: PubMed Central - PubMed

Affiliation: Institut de Recherche pour le Développement, Unité Mixte de Recherche Diversité Adaptation et Développement des Plantes, Montpellier, France.

ABSTRACT
Lead is a heavy metal of particular concern with respect to environmental quality and health. The lack of plant species that accumulate and tolerate Pb is a limiting factor to understand the molecular mechanisms involved in Pb tolerance. In this study we identified Hirschfeldia incana, a Brassicaceae collected from metalliferous mine spoils in Morocco, as a Pb accumulator plant. H. incana exhibited high Pb accumulation in mine soils and in hydroponic cultures. Major Pb accumulation occurred in the roots and a part of Pb translocated from the roots to the shoots, even to the siliques. These findings demonstrated that H. incana is a Pb accumulator species. The expression of several candidate genes after Pb-exposure was measured by quantitative PCR and two of them, HiHMA4 and HiMT2a, coding respectively for a P1B-type ATPase and a metallothionein, were particularly induced by Pb-exposure in both roots and leaves. The functional characterization of HiHMA4 and HiMT2a was achieved using Arabidopsis T-DNA insertional mutants. Pb content and primary root growth analysis confirmed the role of these two genes in Pb tolerance and accumulation. H. incana could be considered as a good experimental model to identify genes involved in lead tolerance and accumulation in plants.

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Related in: MedlinePlus

Lead distribution in different parts of H. incana.Lead contents are expressed as (A) mg Pb.g−1 DW or (B) mg Pb.organ−1. Seedlings were grown for 2 months in hydroponic conditions supplied weekly with fresh media containing 100 µM Pb(NO3)2. Roots R = roots at the rosette stage; Roots F = roots at the floral stage; R leaves = rosette leaves; S leaves = stem leaves. Data are the average (± SE) of three independent measurements.
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pone-0061932-g004: Lead distribution in different parts of H. incana.Lead contents are expressed as (A) mg Pb.g−1 DW or (B) mg Pb.organ−1. Seedlings were grown for 2 months in hydroponic conditions supplied weekly with fresh media containing 100 µM Pb(NO3)2. Roots R = roots at the rosette stage; Roots F = roots at the floral stage; R leaves = rosette leaves; S leaves = stem leaves. Data are the average (± SE) of three independent measurements.

Mentions: In order to evaluate the distribution of Pb in different parts of the plant, H. incana was grown in hydroponic conditions supplied weekly with fresh medium containing 100 µM Pb(NO3)2. After 2 months of Pb exposure, H incana was able to accumulate up to 106 and 77 mg Pb.g−1 DW in roots at the vegetative stage and in roots at the floral stage respectively (Figure 4A). The aerial plant organ with the highest Pb concentration was the rosette leaves reaching up to 0.95 mg.g−1 DW following by the siliques where the Pb content may reach 0.65 mg.g−1 DW. When data were expressed per organ (Figure 4B), strong accumulation of Pb was also observed in the roots (19 and 23.7 mg Pb in roots at the vegetative stage and in roots at the floral stage respectively) but a significant presence of Pb has also been noted in the shoots (0.54 mg Pb in the rosette leaves). These results confirm that the highest amount of lead accumulated in studied plants stays at the root level as described above but an important translocation of Pb can be observed from the roots to the leaves and even to the siliques.


Lead tolerance and accumulation in Hirschfeldia incana, a Mediterranean Brassicaceae from metalliferous mine spoils.

Auguy F, Fahr M, Moulin P, Brugel A, Laplaze L, Mzibri ME, Filali-Maltouf A, Doumas P, Smouni A - PLoS ONE (2013)

Lead distribution in different parts of H. incana.Lead contents are expressed as (A) mg Pb.g−1 DW or (B) mg Pb.organ−1. Seedlings were grown for 2 months in hydroponic conditions supplied weekly with fresh media containing 100 µM Pb(NO3)2. Roots R = roots at the rosette stage; Roots F = roots at the floral stage; R leaves = rosette leaves; S leaves = stem leaves. Data are the average (± SE) of three independent measurements.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3646990&req=5

pone-0061932-g004: Lead distribution in different parts of H. incana.Lead contents are expressed as (A) mg Pb.g−1 DW or (B) mg Pb.organ−1. Seedlings were grown for 2 months in hydroponic conditions supplied weekly with fresh media containing 100 µM Pb(NO3)2. Roots R = roots at the rosette stage; Roots F = roots at the floral stage; R leaves = rosette leaves; S leaves = stem leaves. Data are the average (± SE) of three independent measurements.
Mentions: In order to evaluate the distribution of Pb in different parts of the plant, H. incana was grown in hydroponic conditions supplied weekly with fresh medium containing 100 µM Pb(NO3)2. After 2 months of Pb exposure, H incana was able to accumulate up to 106 and 77 mg Pb.g−1 DW in roots at the vegetative stage and in roots at the floral stage respectively (Figure 4A). The aerial plant organ with the highest Pb concentration was the rosette leaves reaching up to 0.95 mg.g−1 DW following by the siliques where the Pb content may reach 0.65 mg.g−1 DW. When data were expressed per organ (Figure 4B), strong accumulation of Pb was also observed in the roots (19 and 23.7 mg Pb in roots at the vegetative stage and in roots at the floral stage respectively) but a significant presence of Pb has also been noted in the shoots (0.54 mg Pb in the rosette leaves). These results confirm that the highest amount of lead accumulated in studied plants stays at the root level as described above but an important translocation of Pb can be observed from the roots to the leaves and even to the siliques.

Bottom Line: The functional characterization of HiHMA4 and HiMT2a was achieved using Arabidopsis T-DNA insertional mutants.Pb content and primary root growth analysis confirmed the role of these two genes in Pb tolerance and accumulation.H. incana could be considered as a good experimental model to identify genes involved in lead tolerance and accumulation in plants.

View Article: PubMed Central - PubMed

Affiliation: Institut de Recherche pour le Développement, Unité Mixte de Recherche Diversité Adaptation et Développement des Plantes, Montpellier, France.

ABSTRACT
Lead is a heavy metal of particular concern with respect to environmental quality and health. The lack of plant species that accumulate and tolerate Pb is a limiting factor to understand the molecular mechanisms involved in Pb tolerance. In this study we identified Hirschfeldia incana, a Brassicaceae collected from metalliferous mine spoils in Morocco, as a Pb accumulator plant. H. incana exhibited high Pb accumulation in mine soils and in hydroponic cultures. Major Pb accumulation occurred in the roots and a part of Pb translocated from the roots to the shoots, even to the siliques. These findings demonstrated that H. incana is a Pb accumulator species. The expression of several candidate genes after Pb-exposure was measured by quantitative PCR and two of them, HiHMA4 and HiMT2a, coding respectively for a P1B-type ATPase and a metallothionein, were particularly induced by Pb-exposure in both roots and leaves. The functional characterization of HiHMA4 and HiMT2a was achieved using Arabidopsis T-DNA insertional mutants. Pb content and primary root growth analysis confirmed the role of these two genes in Pb tolerance and accumulation. H. incana could be considered as a good experimental model to identify genes involved in lead tolerance and accumulation in plants.

Show MeSH
Related in: MedlinePlus