UNASSIGNED: Anthropogenic activities have led to a widespread @entity595 (U) contamination in many countries. The toxic effects of U at the cellular level have mainly been investigated at a pH around 5.5, the optimal pH for hydroponically grown plants. However, since the speciation of U, and hence its @entity137 , is strongly dependent on environmental factors such as the pH, it is important to investigate the effects of U at different environmentally relevant pH levels. Although U is poorly translocated from the roots to the shoots, resulting in a low U concentration in the leaves, it has been demonstrated that toxic effects in the leaves were already visible after 1 day exposure at pH 5.5, although only when exposed to relatively high U concentrations (100   M). Therefore, the present study aimed to analyse the effects of different U concentrations (ranging from 0 to 100   M) at pH 4.5 in leaves of @entity958 plants. Results indicate that U induces early senescence in A.  thaliana leaves as was suggested by a decreased expression of @entity44891 accompanied by an induction of @entity44890 expression, a decreased CAT capacity and an increased lipid peroxidation. In addition, miRNA398b/c is involved in the regulation of the SOD response in the leaves. As such, an increased @entity68069 /c expression was observed leading to a decreased transcript level of @entity68070 . Finally, the biosynthesis of @entity9050 was induced after U exposure. This can point towards an important role for this metabolite in the scavenging of reactive @entity26 species under U stress.

Oxidative stress responses induced by @entity595 exposure at low pH in  leaves of XXXX plants.

@entity137 :: ('MESH:D064420', 'Disease') :: ['toxicity'] @entity44890 :: ('838651(Tax:3702)', 'Gene') :: ['CAT3'] @entity44891 :: ('842170(Tax:3702)', 'Gene') :: ['CAT2'] @entity68069 :: ('5008210(Tax:3702)', 'Gene') :: ['MIR398b'] @entity68070 :: ('837405;817365', 'Gene') :: ['CSD1/2'] @entity958 :: ('3702', 'Species') :: ['Arabidopsis thaliana'] @entity26 :: ('MESH:D010100', 'Chemical') :: ['oxygen'] @entity595 :: ('MESH:D014501', 'Chemical') :: ['uranium'] @entity9050 :: ('CHEBI:38290', 'Chemical') :: ['ascorbate']
@entity958 :: (3702,Species) :: ['Arabidopsis thaliana']
