Expression profiling of ZmSUN genes by Solexa tag-based and whole-transcriptome sequencing. mRNA from various B73 tissues was subjected to two Solexa sequencing platforms, Solexa whole-transcriptome (SWT) and Solexa dual-tag based (STB). The vertical axis represents the number of 36-nt (SWT) or 21-nt (STB) sequence tag matches per ten million transcripts. (A) Expression levels of ZmSUN genes and the control gene, cytoplasmic GAPDH, are graphed for comparison. (B) The same data are plotted as semi-log2 for easier comparisons among the low-expression ZmSUN genes.