Spatially-constrained growth enhances conversional meltdown
Spatially-constrained growth enhances conversional meltdown
复制标题
空间受限的增长加剧了转型崩溃
DOI：
10.1101/027292
复制
发表时间：
2015
期刊：
影响因子：
--
通讯作者：
A. Murray
中科院分区：
文献类型：
--
作者：
M. Lavrentovich;Mary E. Wahl;D. Nelson;A. Murray
突变或致力于特定功能（分化）的细胞通常会经历实际上不可逆的转化。转化细胞的缓慢生长可以作为一种选择形式，平衡单向转化以将两种细胞类型保持在稳态比率。然而，当单向转换被选择不充分抵消时，原始细胞类型最终将丢失，通常对群体的整体适应性产生负面影响。保存未转化细胞所需的选择和转化之间的关键平衡以及细胞类型之间的稳态比率取决于细胞增殖的空间环境。我们目前的实验数据酵母菌株工程进行不可逆的转换：这种合成系统允许细胞类型特异性荧光标记和外源性变异的相对生长和转化率。我们发现，在脂肪琼脂表面生长的种群比混合良好的种群更容易通过转化引起的“熔化”而丧失脂肪。然后，我们提出了分析预测的增长在几个生物相关的几何形状-混合良好的液体介质，径向扩展的二维殖民地，在两个维度的线性战线-通过采用类比从非平衡统计物理的定向渗滤过渡。这些简化的理论与实验结果是一致的。
Cells that mutate or commit to a specialized function (differentiate) often undergo conversions that are effectively irreversible. Slowed growth of converted cells can act as a form of selection, balancing unidirectional conversion to maintain both cell types at a steady-state ratio. However, when one-way conversion is insuffciently counterbalanced by selection, the original cell type will ultimately be lost, often with negative impacts on the population’s overall ftness. The critical balance between selection and conversion needed for preservation of unconverted cells and the steady-state ratio between cell types depends on the spatial circumstances under which cells proliferate. We present experimental data on a yeast strain engineered to undergo irreversible conversion: this synthetic system permits cell type-specifc fuorescent labeling and exogenous variation of the relative growth and conversion rates. We fnd that populations confned to grow on a fat agar surface are more susceptible than their well-mixed counterparts to ftness loss via a conversion-induced “meltdown.” We then present analytical predictions for growth in several biologically-relevant geometries – well-mixed liquid media, radially-expanding two-dimensional colonies, and linear fronts in two dimensions – by employing analogies to the directed percolation transition from non-equilibrium statistical physics. These simplifed theories are consistent with the experimental results.
DOI：
10.1038/002186a0
发表时间：
1867-06
期刊：
The Chicago Medical Journal
影响因子：
--
作者：
G. D.
通讯作者：
G. D.
影响因子：
2
作者：
Korolev KS;Müller MJ;Karahan N;Murray AW;Hallatschek O;Nelson DR
通讯作者：
Nelson DR