Summary of pollen development transcriptome data for selected essential genes^a.

aBased on published, large-scale microarray datasets for wild-type plants [42]–[44]. bNon-redundant genes with embryo arrest stage shown; no gametophyte defects observed. cModerate (EMG and GEM) and severe (GAM) classes are described in the text. dPercentages of essential genes with transcript detected are noted. Total number of genes analyzed: preglobular (23/25); globular (42/50); moderate (42/48); severe (51/59). Excluded genes were not part of the microarray dataset or had no transcript detected during pollen development. eLevel detected was among top 50% of all transcript levels recorded. fLevel detected was among top 25% of all transcript levels recorded. This cutoff value for detection [42] gave results more consistent with those obtained elsewhere [43], [44]. gMost of the genes identified with a positive signal using data from one laboratory were the same as those identified using data from the other laboratories.