TY - JOUR
T1 - Expression of the Arabidopsis metallothionein 2b enhances arsenite sensitivity and root to shoot translocation in tobacco.
AU - Grispen, V.M.J.
AU - Irtelli, B.
AU - Hakvoort, H.W.J.
AU - Vooijs, R.
AU - Bliek, M.
AU - ten Bookem, W.M.
AU - Verkleij, J.A.C.
AU - Schat, H.
PY - 2009
Y1 - 2009
N2 - We expressed the AtMT2b gene under the 35 S cauliflower mosaic virus promoter in Nicotiana tabacum (Sr1), using leaf disc transformation. Arsenite tolerance and uptake, as well as arsenite-induced phytochelatin (PC) accumulation in roots were measured in transgenic lines, and compared to untransformed ('wild type') tobacco. Measured after 5 days of exposure, arsenite tolerance was slightly but significantly decreased in the transgenic lines compared to wild type. The highest AtMT2b expressing line exhibited a significantly decreased arsenic accumulation in roots, but an increased accumulation in shoots, while the total amount of arsenic taken up remained unchanged, suggesting that AtMT2b expression enhanced the arsenic root to shoot transport. The same transformant line also exhibited a decreased rate of phytochelatin accumulation in the roots, but the phytochelatin-SH to As molar ratio was higher than in wild type, suggesting that the lower arsenite tolerance in the transformant lines was not due to a potential shortage of cysteine for PC synthesis, imposed by expression of the transgene. © 2009 Elsevier B.V. All rights reserved.
AB - We expressed the AtMT2b gene under the 35 S cauliflower mosaic virus promoter in Nicotiana tabacum (Sr1), using leaf disc transformation. Arsenite tolerance and uptake, as well as arsenite-induced phytochelatin (PC) accumulation in roots were measured in transgenic lines, and compared to untransformed ('wild type') tobacco. Measured after 5 days of exposure, arsenite tolerance was slightly but significantly decreased in the transgenic lines compared to wild type. The highest AtMT2b expressing line exhibited a significantly decreased arsenic accumulation in roots, but an increased accumulation in shoots, while the total amount of arsenic taken up remained unchanged, suggesting that AtMT2b expression enhanced the arsenic root to shoot transport. The same transformant line also exhibited a decreased rate of phytochelatin accumulation in the roots, but the phytochelatin-SH to As molar ratio was higher than in wild type, suggesting that the lower arsenite tolerance in the transformant lines was not due to a potential shortage of cysteine for PC synthesis, imposed by expression of the transgene. © 2009 Elsevier B.V. All rights reserved.
U2 - 10.1016/j.envexpbot.2008.12.021
DO - 10.1016/j.envexpbot.2008.12.021
M3 - Article
VL - 66
SP - 69
EP - 73
JO - Environmental and Experimental Botany
JF - Environmental and Experimental Botany
SN - 0098-8472
ER -