Figure 5.

At CFM2 Insertion Mutants.

(A) T-DNA insertions in At CFM2 (At3g01370). Exons and introns are indicated with black rectangles and thin lines, respectively. The positions of the T-DNA insertions in At cfm2-1 (SALK_000703) and At cfm2-2 (SAIL_67_E05) are indicated by filled triangles. Arrows show the primers used for RT-PCR (D). LB, T-DNA left border.

(B) Phenotypes conditioned by At CFM2 mutations. Siliques resulting from self-pollination of an At cfm2-1/+ plant are shown at top. White seeds in a young silique and brown shriveled seeds in an older silique are indicated with arrows. These shriveled seeds germinate poorly; those that germinate yield stunted roots and either no shoot (data not shown) or albino, stunted shoots as shown in (C). Shown below are the phenotypes of a homozygous At cfm2-2 mutant and a heteroallelic plant harboring both mutant alleles. Plants were grown for 17 d on MS medium containing 2% sucrose in cycles of 14 h light/10 h dark. Bars = 5 mm.

(C) Phenotype of rare At cfm2-1 homozygote that developed leaves. Plants were grown for 25 d on MS medium containing 2% sucrose in cycles of 10 h light/14 h dark. An At cfm2-2 homozygote grown in parallel is shown for comparison. Bars = 5 mm

(D) RT-PCR analysis of At CFM2 mRNA in At CFM2 mutants. Two hundred nanograms of total leaf RNA from plants with the indicated genotype (homozygous unless otherwise indicated) was analyzed by RT-PCR using the primer pairs indicated to the left and diagrammed in (A). At crs1-1 mutants were analyzed to show the level of At CFM2 mRNA in a different nonphotosynthetic mutant. Dilutions of the wild-type sample were analyzed to illustrate the relationship between signal intensity and input RNA level. RT-PCR of actin 2 mRNA was used as an internal control. The PCR products were detected by staining with ethidium bromide. –RT, control reaction lacking reverse transcriptase.