Tzur Amit, Kafri Ran, LeBleu Valerie S, Lahav Galit, Kirschner Marc W
Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA.
Science. 2009 Jul 10;325(5937):167-71. doi: 10.1126/science.1174294.
A long-standing question in biology is whether there is an intrinsic mechanism for coordinating growth and the cell cycle in metazoan cells. We examined cell size distributions in populations of lymphoblasts and applied a mathematical analysis to calculate how growth rates vary with both cell size and the cell cycle. Our results show that growth rate is size-dependent throughout the cell cycle. After initial growth suppression, there is a rapid increase in growth rate during the G1 phase, followed by a period of constant exponential growth. The probability of cell division varies independently with cell size and cell age. We conclude that proliferating mammalian cells have an intrinsic mechanism that maintains cell size.
生物学中一个长期存在的问题是，后生动物细胞中是否存在协调生长和细胞周期的内在机制。我们研究了淋巴母细胞群体中的细胞大小分布，并应用数学分析来计算生长速率如何随细胞大小和细胞周期而变化。我们的结果表明，在整个细胞周期中，生长速率都依赖于细胞大小。在最初的生长抑制之后，G1期的生长速率迅速增加，随后是一段持续的指数生长时期。细胞分裂的概率与细胞大小和细胞年龄独立变化。我们得出结论，增殖的哺乳动物细胞具有维持细胞大小的内在机制。
