Mining for genes expressed in patterns consistent with primitive streak, and epiblast differentiation programs. (A) GeneSpring representation of epiblast and streak gene expression profiles during EB differentiation in 10% serum or serum-freeB4L culture. The up-regulation of genes between days 2–4 were similar under both conditions. (B) qRT-PCR analysis of Mixl, Lim1, Cdx4 and Riken clone 8430415E04Rik. The Y-axis represents expression relative to the housekeeping gene HPRT. Error bars indicate ± SD from three biological replicates. (C) 102 genes transiently up regulated during the first 4 days of ES cell differentiation were clustered using a tree algorithm and Pearson correlation of > 0.9. The 'Brief' group represents gene with very transient expression at day 3. (D) Coding region for 8430415E04Rik. The shaded areas represent the three Heat domains.