Global transcriptional response of MEFs to LPA. Gene expression patterns induced by LPA (5 μM) clustered into 10 different classes (K-means clustering analysis; N = 10). Clusters were generated based on the time point of maximal induction. Data indicate 2log ratios of transcripts with p ≤ 0.001 in at least two consecutive time points (resulting in 633 selected transcripts). Each column represents one time point of LPA treatment; the last column shows the expression in non-synchronized MEFs. The time point or period of maximal induction (red) or reduction (green) is indicated in each cluster by an arrow and the respective hour. Solid lines (pink) indicate the median temporal pattern of expression; dotted lines indicate the median level for each cluster. See additional files 2 and 3 for details of the individual clusters.