Cell Growth and Size Homeostasis in Proliferating Animal Cells

Abstract

Size Matters: Cells of different types come in different sizes. Size is established by a trade-off of growth and division; as a result, the distribution of cell size in a population is held stable over time. A classic question in cell physiology is whether the growth rate of cells is constant over time or whether, as cells grow bigger during the cell cycle, they grow faster and faster. Using experimental and mathematical approaches, Tzur et al. (p. 167 ; see the Perspective by Edgar and Kim ) show that the growth rate of mouse lymphoblastoid cells in culture is slow in the G ₁ phase and then increases to reach a constant exponential rate. Thus, there is an active size-control mechanism that limits size variation in animal cells.