Fig. 2.

Rescue of Arabidopsis thiC mutants. (A) (Left) Rescue of thiC by supplementation with thiamin after transfer to soil. Ten-day-old segregating thiC seedlings grown on medium lacking vitamin B1 (see Fig. 1D) were transferred to soil and watered with the indicated concentrations of thiamin (μM). Plants are 30 days after transfer to soil. (Right) Total vitamin B1 content of seeds of rescued plants. (B) Progeny of rescued thiC lines as described in A compared with segregating nonsupplemented thiC from a heterozygous population. The numbers indicate the concentration of thiamin (μM) supplied to the mother plants. Seedlings (10 days old) were grown in the absence of vitamin B1. As a control, a segregating thiC seedling from a heterozygous mother grown in the presence of vitamin B1 is shown. (C) Total vitamin B1 content of WT (circles), thiC progeny rescued with 100 μM (squares) and 1.5 μM (triangles) thiamin, respectively, grown in the absence of thiamin over the time period indicated. (D) Total chlorophyll content (Chl) of the same seedlings as in C. Error bars (some of which are sufficiently small that they fall within the symbols) indicate the standard deviation of three independent experiments. DAG, days after germination.