Fig. 4: astol1 mutant enhances S and Se uptake and phytochelatins-dependent As detoxification.

a Metabolic pathway from serine to cysteine. b Relative fold change of S-related metabolites in astol1(+/−) compared to WT, visualized as the heat map (n = 5 biological replicates for sulfate, three biological replicates for all other metabolites; each biological replicate represents an individual plant). Abbreviations of metabolites: SO₄²⁻sulfate, Ser serine, OAS O-acetylserine, Cys cysteine, Cyst cystathionine, GSH glutathione, Hcy homocysteine, Met methionine, SAH S-adenosylhomocysteine, SAM S-adenosylmethionine, MTA methylthioadenosine. c Relative expression levels of rice genes involved in sulfate uptake and reduction in the roots and shoots of 3-week-old WT and astol1(+/−). Transcriptional induction of selected rice genes (OsSULTR1;1 (Os03g0195800) in roots, OsAPR1 (Os07g0509800) and OsSiR (Os05g0503300) in roots and shoots) was measured by Q-PCR, with OsHistone H3 as the internal reference gene. d S concentrations in roots and shoots of 5-week-old WT and astol1(+/−). e Se concentrations in roots and shoots of 5-week-old WT and astol1(+/−) exposed to 2 μM Se(VI) for 3 days. The concentrations of non-protein thiols in roots (f) and shoots (g) of 4-week-old WT and astol1(+/−) treated with 5 μM As(III) for 3 days. DW, dry weight. FW, fresh weight. WT, wild type. astol1(+/−), astol1 heterozygote. Data in c–g are shown as means ± s.d. n = 3 (c, d), 4 (e) or 5 (f, g) biological replicates; each biological replicate represents an individual plant. Asterisks in b–g indicate significant differences by two-sided Student’s t test: *P < 0.05, **P < 0.01, ***P < 0.001.