Figure 2.

(A) K-means clustering of 685 highly differentially expressed genes resulted in five distinct temporal expression patterns. mRNA expression is depicted as fold increase over the mean expression during depicted developmental stages. (B) Validation of GeneChip data and clustering method by comparing expression data obtained with GeneChip (dotted lines) vs. Q-PCR (solid lines) for genes with a known expression profile representative for their cluster. Data are expressed as the level of change compared to the minimal expression measured for the given gene. Standard deviations were calculated from triplicate experiments. (R) Correlation coefficient for GeneChip vs. Q-PCR data.