The proportional scaling of mRNA and ribosome concentrations controls eukaryotic cell growth.

Ribosome and mRNA concentrations scale proportionally with growth rate, enabling eukaryotic cells like Saccharomyces cerevisiae to accelerate proliferation efficiently.

• Why it matters: Understanding how cell growth is regulated at the molecular level is crucial for insights into eukaryotic physiology and disease, yet the principles governing this process are not fully understood.
• What they did: The study used single-molecule ribosome tracking, spike-in RNA sequencing, and proteomics across 15 nutrient conditions to quantify how mRNA and ribosome levels change with growth rate, supported by a kinetic model of mRNA-ribosome interactions.
• The result: Findings show that increasing mRNA and ribosome concentrations proportionally boosts growth, with constant peptide elongation speed, providing a quantitative framework for eukaryotic biosynthesis regulation.