Boehm Christian R, Grant Paul K, Haseloff Jim
Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK.
Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Germany.
Nat Commun. 2018 Feb 22;9(1):776. doi: 10.1038/s41467-018-03069-3.
Modern genetic tools allow the dissection and emulation of fundamental mechanisms shaping morphogenesis in multicellular organisms. Several synthetic genetic circuits for control of multicellular patterning have been reported to date. However, hierarchical induction of gene expression domains has received little attention from synthetic biologists, despite its importance in biological self-organization. Here we report a synthetic genetic system implementing population-based AND-logic for programmed autonomous induction of bacterial gene expression domains. We develop a ratiometric assay for bacteriophage T7 RNA polymerase activity and use it to systematically characterize different intact and split enzyme variants. We then utilize the best-performing variant to build a three-color patterning system responsive to two different homoserine lactones. We validate the AND gate-like behavior of this system both in cell suspension and in surface culture. Finally, we use the synthetic circuit in a membrane-based spatial assay to demonstrate programmed hierarchical patterning of gene expression across bacterial populations.
现代遗传工具能够剖析和模拟多细胞生物中塑造形态发生的基本机制。迄今为止，已经报道了几种用于控制多细胞模式形成的合成遗传电路。然而，基因表达域的分级诱导尽管在生物自组织中具有重要意义，但却很少受到合成生物学家的关注。在这里，我们报告了一个合成遗传系统，该系统实现了基于群体的与逻辑，用于细菌基因表达域的程序性自主诱导。我们开发了一种用于噬菌体T7 RNA聚合酶活性的比率测定法，并使用它来系统地表征不同的完整和分裂酶变体。然后，我们利用性能最佳的变体构建一个对两种不同的高丝氨酸内酯有反应的三色图案系统。我们在细胞悬浮液和表面培养中验证了该系统的与门样行为。最后，我们在基于膜的空间测定中使用合成电路，以证明细菌群体中基因表达的程序性分级图案形成。
