Physics Department, University of Maryland, College Park, MD, USA.
Phys Biol. 2011 Oct;8(5):055001. doi: 10.1088/1478-3975/8/5/055001. Epub 2011 Aug 10.
The shape and motion of cells can yield significant insights into the internal operation of a cell. We present a simple, yet versatile, framework that provides multiple metrics of cell shape and cell shape dynamics. Analysis of migrating Dictyostelium discoideum cells shows that global and local metrics highlight distinct cellular processes. For example, a global measure of shape shows rhythmic oscillations suggestive of contractions, whereas a local measure of shape shows wave-like dynamics indicative of protrusions. From a local measure of dynamic shape, or boundary motion, we extract the times and locations of protrusions and retractions. We find that protrusions zigzag, while retractions remain roughly stationary along the boundary. We do not observe any temporal relationship between protrusions and retractions. Our analysis framework also provides metrics of the boundary as whole. For example, as the cell speed increases, we find that the cell shape becomes more elongated. We also observe that while extensions and retractions have similar areas, their shapes differ.
细胞的形状和运动可以提供对细胞内部运作的重要见解。我们提出了一个简单而通用的框架，提供了多种细胞形状和细胞形状动态的度量。对迁移的盘基网柄菌细胞的分析表明，全局和局部度量突出了不同的细胞过程。例如，形状的全局度量显示出有节奏的振荡，提示收缩，而形状的局部度量显示出波状动力学，提示突起。从动态形状的局部度量或边界运动中，我们提取出突起和收缩的时间和位置。我们发现突起呈之字形，而收缩沿边界大致保持静止。我们没有观察到突起和收缩之间存在任何时间关系。我们的分析框架还提供了边界整体的度量。例如，随着细胞速度的增加，我们发现细胞形状变得更加细长。我们还观察到，虽然扩展和收缩具有相似的面积，但它们的形状不同。
