Early-replicating genes are overexpressed during S phase. (A) The dosage between early- and late-replicating genes is predicted to be imbalanced during mid-S phase because early-replicating genes have finished replication and late-replicating ones have not yet started. (B) Early-replicating genes are overexpressed during mid-S phase. The observed (blue) average expression ratio of all gene pairs in each S-phase subgroup was normalized by that in G1/S. The random expectation (orange) was obtained from 2000 “pseudo” early- or “pseudo” late-replicating genes that were randomly sampled from the genome. Error bars represent the standard errors among gene pairs in each subgroup. (C) The distribution of the expression ratio of early- to late-replicating gene in each gene pair in subgroup 4.
