Summary
Early embryonic development is characterized by a dramatic transition from cellular dependence on RNAs that were in the egg prior to fertilization to RNAs produced by the embryo itself. This process is known as zygotic genome activation (ZGA). The timing of ZGA is linked to changes in cell size, specifically the ratio of nuclear content (DNA) to cytoplasmic volume (also known as the nuclear-to-cytoplasmic or N/C ratio), which increases as cells replicate their DNA without growth. How cells measure this ratio and use it to control gene expression is a fundamental biological question that remain
