Evaluation of DNA damage and mutagenicity induced by lead in tobacco plants

0307201 - ÚEB 2008 RIV NL eng J - Článek v odborném periodiku
Gichner, Tomáš - Žnidar, I. - Száková, J.
Evaluation of DNA damage and mutagenicity induced by lead in tobacco plants.
[Hodnocení poškození DNA a mutagenity po aplikaci olova u rostlin tabaku.]
Mutation Research - Genetic Toxicology and Environmental Mutagenesis. Roč. 652, č. 2 (2008), s. 186-190. ISSN 1383-5718. E-ISSN 1879-3592
Grant CEP: GA ČR GA521/05/0500
Výzkumný záměr: CEZ:AV0Z50380511
Zdroj financování: V - jiné veřejné zdroje
Klíčová slova: Comet assay * Nicotiana tabacum L. var. xanthi * Single-cell gel electrophoresis * Somatic mutations
Kód oboru RIV: EB - Genetika a molekulární biologie
Impakt faktor: 2.363, rok: 2008

Tobacco (Nicotiana tabacum L. var. xanthi) seedlings were treated with aqueous solutions of lead nitrate (Pb2+) at concentrations ranging from 0.4 mM to 2.4 mM for 24 h and from 25 μM to 200 μM for 7 days. The DNA damage measured by the comet assay was high in the root nuclei, but in the leaf nuclei a slight but significant increase in DNA damage could be demonstrated only after a 7-day treatment with 200 μM Pb2+. In tobacco plants growing for 6 weeks in soil polluted with Pb2+ severe toxic effects, expressed by the decrease in leaf area, and a slight but significant increase in DNA damage were observed. The tobacco plants with increased levels of DNA damage were severely injured and showed stunted growth, distorted leaves and brown root tips. The frequency of somatic mutations in tobacco plants growing in the Pb2+-polluted soil did not significantly increase. Analytical studies by inductively coupled plasma optical emission spectrometry demonstrate that after a 24-h treatment of tobacco with 2.4 mM Pb2+, the accumulation of the heavy metal is 40-fold higher in the roots than in the above-ground biomass. Low Pb2+ accumulation in the above-ground parts may explain the lower levels or the absence of Pb2+-induced DNA damage in leaves.

Semenáčky tabáku (Nicotiana tabacum var. xanthi) byly ovlivněny roztoky Pb (NO3)2 po dobu 24 h a 7 dní. Průkazné zvýšení poškození DNA, měřeno kometovým testem, bylo prokázáno pouze v kořenech semenáčku. Po kultivaci semenáčků tabáku v pudě kontaminované Pb (NO3)2 po dobu 6 týdnů bylo zvýšení poškození DNA vždy spojeno se silnou toxicitou (inhibice růstu semenáčků, nahnědlé a zdeformované listy). Zvýšení frekvence somatických mutací nebylo prokázáno. Zvýšení poškozené DNA je pravděpodobně podmíněné nekrotickou fragmentací DNA.
Trvalý link: http://hdl.handle.net/11104/0160034