Figure 2.

GRXS15 K83A mutation has no impact on the biotin pathway in Arabidopsis seedlings. A, Immunoblot analysis of biotinylated MCCA in mitochondria (mito) of GRXS15 K83A mutants compared with WT. In the upper, biotinylated MCCA was detected by streptavidin HRP in isolated mito from 2-week-old seedlings (9 μg protein was loaded per lane). In the lower, amido black staining of the membrane is shown as a control for protein loading. B and C, Fatty acids quantified by gas chromatography of 8-d-old seedlings (B) and seeds (C) of GRXS15 K83A line #4 compared to WT (n = 3–4; means ± sd). The statistical analysis (two-way ANOVA with post hoc Holm–Sidak comparisons for WT versus grxs15) indicated no significant (P ≤ 0.05) change except for 18:3 (***P < 0.001). D, GRXS15 K83A line #4, the knockdown line GRXS15^amiR (amiR), and WT plants were grown on horizontal plates with 1/2 MS agar without sucrose. The medium contained either no biotin (control), 1 μM biotin or 1 μM desthiobiotin.