Chung J D, Stephanopoulos G
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139.
Biotechnol Bioeng. 1995 Jul 20;47(2):234-42. doi: 10.1002/bit.260470215.
Using a flow cytometry-based technique for detecting p-galactosidase. lacZ fusions have been used to study the pattern of gene expression exhibited by stationary phase cultures of Bacillus subtilis that have initiated the developmental pathway of spore formation. We have found that within such cultures there exist two distinct cell types: one that has induced the developmental program of gene expression and one that has not. This heterogeneity among transcriptional states is shown to be established early during the stationary phase and plays a significant role in influencing later stationary phase events. Additionally, when this technique is used to study gene expression in mutants that display altered patterns of gene expression, we are able to conclude that the cellular apparatus responsible for sensing and transducing stationary phase developmental signals represents a bottleneck that controls the expression of certain early stationary phase genes. These findings provide a demonstration of the utility of single cell measurements of gene expression and indicate that unless culture heterogeneity is properly taken into account, standard measurements of gene expression may not provide information suitable for the analysis of events occurring at the cellular level. (c) 1995 John Wiley & Sons, Inc.
利用基于流式细胞术的技术检测β-半乳糖苷酶。lacZ融合蛋白已被用于研究枯草芽孢杆菌稳定期培养物所展现的基因表达模式，这些培养物已启动了孢子形成的发育途径。我们发现，在这样的培养物中存在两种不同的细胞类型：一种诱导了基因表达的发育程序，另一种则没有。转录状态的这种异质性在稳定期早期就已确立，并在影响后期稳定期事件中发挥重要作用。此外，当使用该技术研究显示出改变的基因表达模式的突变体中的基因表达时，我们能够得出结论，负责感知和转导稳定期发育信号的细胞机制代表了一个控制某些早期稳定期基因表达的瓶颈。这些发现证明了基因表达单细胞测量的实用性，并表明除非适当地考虑培养物的异质性，否则基因表达的标准测量可能无法提供适合分析细胞水平事件的信息。(c) 1995约翰·威利父子公司
