Figure 1.—

Analysis of differential gene expression in B73 and Mo17. Signal correlation plots were used to examine intraspecific variation, parental effects, and inbred–hybrid comparisons in immature ear tissue (similar plots for embryo and seedling tissue are available in supplemental data at http://www.genetics.org/supplemental/). (A) The average signal derived from the three biological replicates of B73 (y-axis) and Mo17 (x-axis) graphed using a logarithmic scale. Note the prevalence of genes showing distinct expression patterns in the two genotypes. (B) A similar graph was made to compare the expression in the two reciprocal F₁ hybrids, B73 × Mo17 (x-axis) and Mo17 × B73 (y-axis). The relative lack of differential expression indicates the lack of parental effects. (C) The average signal for B73 and Mo17 inbred lines (thus, the midparent level) was determined and plotted along the y-axis while the average signal from the reciprocal F₁ hybrids was plotted along the x-axis. The high correlation of these two plots supports a trend toward midparent expression in the F₁ hybrid.