Figure 3.

(A) Southern blots of a family from the F₇ generation segregating for the mop1 mutation as well as the presence of MuDR(p1)*. The same blot was probed for Mu1 and then stripped and reprobed with TIRA. The genotype of each individual is indicated. Individuals that genotype as mop1 homozygous (“*”) are hypomethylated at both Mu1 and TIRA. Individuals that are mop1 heterozygous are methylated at both Mu1 and TIRA. Individuals that lack MuDR(p1)* are missing fragments corresponding to both methylated and hypomethylated TIRA. Active MuDR(p1) and MuDR(p1)* silenced by Muk are presented as controls. (B) Ear progeny of a cross between indicated individuals represented by the Southern blot by a mop1/+ tester. Individuals that are mop1/mop1;MuDR(p1)* gave rise to ∼36% spotted kernels when crossed to mop1/+. Conversely, individuals that are mop1/+;MuDR(p1)* gave rise to very few spotted kernels when crossed to mop1/+. Individuals lacking MuDR(p1)*, regardless of mop1 phenotype, gave rise to no spotted kernels.