Figure 6.

THF1 Is Involved in d-Glucose Signaling.

(A) Scheme of the T-DNA insertion (SALK line 094925) in THF1, as described previously (Wang et al., 2004). LB, left border; RB, right border.

(B) Seedlings of Columbia, gpa1-4, and thf1-1germinated on both 1% and 6% d-glucose, showing the sensitivity of the thf1-1 mutant to increased d-glucose compared with both the wild type and gpa1-4. Images show randomly selected seedlings taken from the pool used for the determination of growth rate. Arrows mark the shoot/root transition and the root tip. The growth rate of roots on increased d-glucose is reduced in thf1-1 seedlings.

(C) Tolerance to high levels of d-glucose can be conferred by overexpression of THF1. The rate of growth of the primary root was assayed over a 3-d period (each set of three bars), beginning 48 h after exposure to light. The interval rate is expressed as millimeters of growth per hour, averaged over each 24-h period. Error bars represent se. n > 10. THF1ox, ectopically overexpressed THF1.