Reconstruction of rat retinal progenitor cell lineages in vitro reveals a surprising degree of stochasticity in cell fate decisions
Reconstruction of rat retinal progenitor cell lineages in vitro reveals a surprising degree of stochasticity in cell fate decisions
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DOI：
10.1242/dev.059683
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发表时间：
2011-01-15
期刊：
影响因子：
4.6
通讯作者：
Cayouette, Michel
中科院分区：
文献类型：
--
作者：
Gomes, Francisco L. A. F.;Zhang, Gen;Cayouette, Michel
脊椎动物视网膜的活体细胞谱系追踪研究表明，视网膜克隆的大小和细胞组成高度不同。要确定这种可变性是否反映了许多不同的视网膜前体细胞(RPC)之间不同但可复制的谱系，或者是在更多相同的RPC群体中随机决定命运的结果，一直是一个具有挑战性的问题。为了开始区分这些可能性，我们开发了一种方法，用于长期视频显微镜跟踪以克隆密度培养的大鼠围产期RPC的谱系。在这种培养中，两个不同克隆之间的细胞间相互作用被消除，细胞外环境保持不变，使我们能够研究给定RPC的细胞内在潜力。对重建的谱系的定量分析表明，RPC的分裂模式与一种简单的随机行为模式惊人地一致，在这种模式中，繁殖或区分的决定是由固定的概率设定的。通过假设在这个阶段产生的四种不同的视网膜细胞类型中的每一种都是通过分化神经元随机选择的，每种类型的相对概率取决于它们在成熟视网膜中的丰度，从而很好地描述了克隆内细胞类型发生的组成和顺序的差异性。尽管克隆内细胞类型的许多可能组合中的一些出现的频率与完全随机模型不兼容，但我们的结果支持这样的概念，即随机性在视网膜发育过程中发挥重要作用，因此可能在中枢神经系统的其他部分发挥作用。
In vivo cell lineage-tracing studies in the vertebrate retina have revealed that the sizes and cellular compositions of retinal clones are highly variable. It has been challenging to ascertain whether this variability reflects distinct but reproducible lineages among many different retinal progenitor cells (RPCs) or is the product of stochastic fate decisions operating within a population of more equivalent RPCs. To begin to distinguish these possibilities, we developed a method for long-term videomicroscopy to follow the lineages of rat perinatal RPCs cultured at clonal density. In such cultures, cell-cell interactions between two different clones are eliminated and the extracellular environment is kept constant, allowing us to study the cell-intrinsic potential of a given RPC. Quantitative analysis of the reconstructed lineages showed that the mode of division of RPCs is strikingly consistent with a simple stochastic pattern of behavior in which the decision to multiply or differentiate is set by fixed probabilities. The variability seen in the composition and order of cell type genesis within clones is well described by assuming that each of the four different retinal cell types generated at this stage is chosen stochastically by differentiating neurons, with relative probabilities of each type set by their abundance in the mature retina. Although a few of the many possible combinations of cell types within clones occur at frequencies that are incompatible with a fully stochastic model, our results support the notion that stochasticity has a major role during retinal development and therefore possibly in other parts of the central nervous system.