Time warping of a single cell cycle. (A-C) Pearson distance matrices constructed for S. cerevisiae - S. pombe microarray time series data. S. cerevisiae cells were synchronized using α-factor S. pombe cells were synchronized using cdc25 temperature sensitive mutant . Periodically arranged patterns mark similarities in the gene expression; bars on the left and the bottom mark cell cycle stages in both species. (A) Raw data, before treatment. (B) Smoothed and filtered data, white line indicates global alignment path, black box marks data range corresponding to a single cell cycle in both species. (C) Similarity matrix for the data range marked by black box in (B), white line indicates the global alignment path. (D) Cell cycle phases were established using standard set of markers, such as histones (S-phase), CDC20, CDCD5 (M-phase), DBF2, CDC6 (M/G1-phase) . Brackets show ranges corresponding to a single cell cycle.