阳离子型载体通过静电作用压缩包载mRNA能够实现高效的基因治疗，但是高生物毒性以及脱靶毒性是制约其临床转化的关键因素。因此亟需建立一种安全的递送策略用于实现精准可控的mRNA基因治疗。DNA纳米结构作为递送载体，能够规避阳离子型载体的高生物毒性，但难以有效包载保护mRNA，而且其极低的内涵体逃逸效率会直接导致无效的mRNA基因治疗。本项目拟通过核酸纳米技术对mRNA进行预捆绑制约，降低mRNA水合粒径，然后将其负载至聚己内酯-DNA刷的交联位点中，与交联剂组装构建DNA纳米凝胶。DNA纳米凝胶能够将mRNA包裹在结构内部，增强mRNA对核酸酶的耐受性。同时在递送载体中引入近红外光热分子，通过时空二维的光照调节作用赋予DNA纳米凝胶内涵体逃逸和蛋白表达行为在空间以及效率上的可控化，最终实现精准可控的mRNA基因治疗。本项目的开展有望为mRNA递送提供新的方法，具有重要的科学意义。

The cationic vectors can compress and protect mRNA drugs via electrostatic interaction to achieve efficient gene therapy, but the serious biotoxicity and off-target toxicity are the crucial factors that prevent the translation of mRNA drugs from fundamental study to clinic use. Therefore, it is urgent to establish a safe and efficient delivery strategy for precise and controllable mRNA gene therapy. As the endogenous macromolecular materials, the DNA nanostructures can avoid the high toxicity of traditional cationic carriers, but the mRNAs possessing large molecular weight are difficultly encapsulated and protected by DNA nanostructures. Moreover, the inefficient endosome escape of DNA nanostructures makes gene therapy unavailability. To circumvent these challenges, herein we propose a mRNA-prebundled strategy via nucleic acid nanotechnology to reduce the hydration size of mRNA, and the DNA-grafted polycaprolactone brush is first loaded with bundled mRNA and then crosslinked by DNA linkers via nucleic acid hybridization to form DNA nanogel, in which the bundled mRNA is embedded and protected inside, thus exhibiting excellent physiological stability against nuclease digestion. And the near-infrared photothermal conversion molecules are introduced within DNA nanogel to provide confined hyperthermia environment inducing to endosome escape. The spatiality and efficiency of endosomal escape and protein expression behaviors can be controlled by adjusting with spatiotemporal two-dimension of illumination. With mRNA-prebundled strategy and spatiotemporal precise optical control technology, the mRNA-embedded DNA nanogels are hopeful to precise gene therapy. Our proposal will provide a promising candidate for mRNA delivery and have important scientific significance.