Fig. 4. RNA variation is not predictive for protein variation.

Patterns of gene expression variation at steady-state in S-phase cells. a Relation between mean RNA expression mean (RPKM) and RNA expression variation (CV²). Colors indicate variably (red) or stably (blue) expressed genes. b Similar to a, but for protein. c Normalized gene expression variation (residuals) at the RNA and protein levels correlate moderately (Spearman’s rho = 0.28). Genes of interest are indicated. d A simple additive model of RNA variation and estimated translation rate effectively predicts protein expression variation (Spearman’s rho = 0.50). A subset of genes from Fig. 3c are included here, as public data were not available to estimate translation rate for all genes of interest.