Dual-Responsive DNA Nanodevice for the Available Imaging of an Apoptotic Signaling Pathway in Situ

Abstract

Fluorescence imaging tools enable the in situ visualization of those molecules involved in various cell signaling pathways, but directly describing these pathways instead of the separate mediators in situ is much more meaningful and still full of challenges. In this work, a dualresponsive DNA nanodevice that allows the available imaging of an apoptotic signaling pathway in living cells has been developed. The nanodevice is constructed through assembling an elaborately designed Y-shaped DNA (Y-DNA) layer on gold nanoparticles (AuNPs). Only if an apoptotic signaling pathway involving the manganese superoxide dismutase (MnSOD) mRNA and downstream cytochrome c (Cyt c) is presented to serve as the input, the nanodevice can perform an "AND" logic gate operation, disassembling the Y-DNA from the AuNP surface and thereafter outputting a fluorescence signal. In comparison with the fluorescence imaging methods that target individual specific molecules, our strategy allows direct profiling of a specific signaling pathway by connected characterization of two correlative targets. The programmable feature of this strategy also shows the potential for the profiling of other signaling pathways. The concept of studying the line connecting two points will contribute to the systematic interrogation on the signaling networks in situ as the networks are composed of lines instead of individual points.

DNA‐Driven Two‐Layer Core–Satellite Gold Nanostructures for Ultrasensitive MicroRNA Detection in Living Cells

“…Plasmonic gold‐based nanomaterials and their assemblies display powerful and tunable optical properties that have been widely investigated for bioapplications. [ 4,6–8 ] Based on Au nanoparticle (NP) probes, miRNA detection has been developed with optical sensing, [ 9 ] electrochemical detection methods, [ 10–12 ] fluorescence‐based detection, [ 13–16 ] and so on. [ 17 ] In recent years, NP‐based self‐assembling structures with enhanced chiroptical properties have been developed for the detection of several important biomarkers (DNA, RNA, proteins, etc.).…”

“…Plasmonic gold-based nanomaterials and their assemblies display powerful and tunable optical properties that have been widely investigated for bioapplications. [4,[6][7][8] Based on Au nanoparticle (NP) probes, miRNA detection has been developed with It is a significant challenge to achieve controllable self-assembly of superstructures for biological applications in living cells. Here, a two-layer core-satellite assembly is driven by a Y-DNA, which is designed with three nucleotide chains that hybridized through complementary sequences.…”

Molecular modification and assembly at cell surface for biochemical analysis

“…细胞凋亡是保守且不可逆的程序性细胞死亡，在生物体内受到严格地调控。 细胞凋亡的激活涉及到错综复杂的信号网络，目前，通过经典的分子生物学技术 已经揭示了部分凋亡信号通路。然而，细胞凋亡相关研究仍然迫切需要研发具有 操作性强、效率高的技术和方法。同时，近年来纳米材料的发展日新月异，其与 多个学科的交叉融合为生化分析新方法研究提供了契机 [74][75][76] 。 以金纳米材料为代 表的贵金属纳米材料，以及磁性纳米材料、聚合物纳米材料、碳纳米材料等因具 有独特的物理化学性质， 因而在减少背景干扰的同时能增强对靶分子信息的获取， 从而提高检测灵敏度 [77][78] 。同时，通过对纳米材料的可控功能化修饰使其具有靶 向性、可降解性、良好的生物相容性等，进一步拓宽了纳米材料在生化分析领域 的应用 [79][80][81] 。为此，我们设计了一种双响应型的 DNA 纳米器件，以寡核苷酸作 为凋亡信号分子的识别元件，将其修饰到金纳米颗粒上，集成并模拟凋亡信号分 子的受体系统，实现了对活细胞中凋亡信号通路的高效成像 [82] 。如图 5 所示， DNA 纳米器件可通过由叶酸受体介导的途径进入细胞，当上游锰超氧化物歧化 application for the available imaging of apoptotic signaling pathway on cells [82] .…”

Target-Initiated Great Change in Electrochemical Steric Hindrance for an Assay of Granzyme B Activity

“…Finally, 20 nm AuNPs were synthesized as the previous work: 30 Briefly, 80 mL of 2.2 mM sodium citrate solution was heated to boiling under vigorous stirring. Then, 533 μL of 25 mM HAuCl 4 was added and allowed to react until the color of the solution changed from yellow to soft pink in 10 min.…”