PDF(Pubmed)
Abstract：
Many animals share a lifelong capacity to adapt their growth rates and body sizes to changing environmental food supplies. However, the cellular and molecular basis underlying this plasticity remains only poorly understood. We therefore studied how the sea anemones Nematostella vectensis and Aiptasia (Exaiptasia pallida) respond to feeding and starvation. Combining quantifications of body size and cell numbers with mathematical modelling, we observed that growth and shrinkage rates in Nematostella are exponential, stereotypic and accompanied by dramatic changes in cell numbers. Notably, shrinkage rates, but not growth rates, are independent of body size. In the facultatively symbiotic Aiptasia, we show that growth and cell proliferation rates are dependent on the symbiotic state. On a cellular level, we found that >7% of all cells in Nematostella juveniles reversibly shift between S/G2/M and G1/G0 cell cycle phases when fed or starved, respectively. Furthermore, we demonstrate that polyp growth and cell proliferation are dependent on TOR signalling during feeding. Altogether, we provide a benchmark and resource for further investigating the nutritional regulation of body plasticity on multiple scales using the genetic toolkit available for Nematostella.
摘要：
许多动物具有终生的能力，可以使它们的生长速度和体型适应不断变化的环境食物供应。然而,这种可塑性背后的细胞和分子基础仍然知之甚少。因此，我们研究了海葵Nematostellavectensis和Aiptasia（Exaiptasiapallida）对进食和饥饿的反应。将身体大小和细胞数量的量化与数学建模相结合，我们观察到线虫的生长和收缩率是指数的，刻板印象，并伴随着细胞数量的急剧变化。值得注意的是,收缩率，但不是增长率，与身体大小无关。在兼性共生的Aiptasia中，我们表明生长和细胞增殖率依赖于共生状态。在细胞层面上，我们发现，>7％的Nematostella幼体细胞在进食或饥饿时在S/G2/M和G1/G0细胞周期阶段之间可逆地转移，分别。此外，我们证明在进食过程中息肉的生长和细胞增殖依赖于TOR信号传导.总之,我们提供了一个基准和资源,用于使用Nematostella的遗传工具包在多个尺度上进一步研究身体可塑性的营养调节.
