Differences in Selenium Uptake, Distribution and Expression of Selenium Metabolism Genes in Tomatoes

Abstract

Effects of different levels of selenium (0, 5 and 10 mgkg -1 ) on selenium uptake, distribution, and the expression levels of Se metabolism genes were compared with three tomato (Solanum lycopersicum L.) varieties (KT30, Defumm-8 and Luobeiqi). The results showed that Se inhibited the expression levels of APS reductase in varieties of KT30 and Luobeiqi; however, there was no significant difference in variety Defumm-8. Selenium also promoted expression levels of ATP sulfurylase of the tomato varieties. The expression levels of cysteine desulfurase of variety KT30 and variety Defumm-8 first decreased and then increased with the increasing Se concentration; however, expression levels of Se were lower than the control, and expression levels of Se in leaves of variety Luobeiqi increased. The Se concentration markedly decreased the expression levels of Sadenosyl-l-Met:l-Met S-methyltransferase in the three varieties, except variety Defumm-8 with Se at 5 mgkg -1 . Furthermore, the Se concentration markedly decreased expression levels of serine acetyltransferase of variety KT30 and variety Defumm-8, but expression levels of leaves of variety Luobeiqi increased. Expression levels of serine acetyltransferase in variety Luobeiqi increased with the increasing Se concentration but decreased in KT30 and Defumm-8. Expression levels of SeCys methyltransferase (SMT) in Luobeiqi and KT30 were reduced by Se, while promoted in Defumm-8. The Se treatment promoted expression levels of APS in three tomato varieties.