School of Mechanical and Advanced Materials Engineering, Ulsan National Institute of Science and Technology, 100 Banyeon-ri, Ulsan 689-798, Republic of Korea.
Biomaterials. 2012 Jan;33(2):624-33. doi: 10.1016/j.biomaterials.2011.09.069. Epub 2011 Oct 19.
We describe a hydrogel patterning and transferring (HPT) method that facilitates the quantitative analysis of synthetically engineered genetic circuits within bacterial cells. The HPT method encapsulates cells in the alginate hydrogel patterns by using polydimethylsiloxane (PDMS) template. Then, the hydrogel-encapsulated cell patterns are transferred onto an agarose hydrogel substrate that encapsulates inducer chemicals or bacterial cells. Using the HPT method, we demonstrate that inducers in the agarose hydrogel substrate regulate gene expression of the patterned cells for qualitative analysis by activating the promoters of fluorescence protein genes. In addition, we demonstrate that the HPT method can be used for the analysis of the cross-talk between genetic circuits and the concentration-dependent gene expression and regulation because the agarose hydrogel substrate can produce concentration gradients of inducers. Lastly, we demonstrate that the HPT method can be applied to investigating intercellular communication between neighboring cells with a wide range of cell densities. Since the HPT method is simple to deal with but versatile and powerful to quantitatively analyze genetic circuits in living cells in many controllable manners, we believe that the method can be widely used for the rapid advancement of synthetic, molecular, and systems biology.
我们描述了一种水凝胶图案化和转移（HPT）方法，该方法可促进对细菌细胞内合成工程遗传回路的定量分析。HPT 方法通过使用聚二甲基硅氧烷（PDMS）模板将细胞包裹在藻酸盐水凝胶图案中。然后，将水凝胶包裹的细胞图案转移到琼脂糖水凝胶基底上，该基底包裹诱导剂化学物质或细菌细胞。使用 HPT 方法，我们证明了琼脂糖水凝胶基质中的诱导剂可以通过激活荧光蛋白基因的启动子来调节图案化细胞的基因表达，从而进行定性分析。此外，我们证明 HPT 方法可用于分析遗传回路之间的串扰以及浓度依赖性基因表达和调控，因为琼脂糖水凝胶基质可以产生诱导剂的浓度梯度。最后，我们证明 HPT 方法可用于研究具有广泛细胞密度的相邻细胞之间的细胞间通讯。由于 HPT 方法简单易用，但功能多样且强大，可以以多种可控方式定量分析活细胞中的遗传回路，因此我们相信该方法将被广泛用于合成、分子和系统生物学的快速发展。
