Rewatkar Prarthana V, Sester David P, Parekh Harendra S, Parat Marie-Odile
School of Pharmacy, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland 4102, Australia.
School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland 4072, Australia.
ACS Biomater Sci Eng. 2016 Mar 14;2(3):438-445. doi: 10.1021/acsbiomaterials.6b00033. Epub 2016 Feb 25.
Asymmetric cationic amino acid-based dendrimers are highly branched chemically derived gene vectors developed to transport cargo such as plasmid DNA across the plasma membrane. We have previously demonstrated their propensity to enter cells that form caveolae, driven by positive charge density and promoted by arginine head groups. Caveolae are plasma membrane subdomains serving a number of cellular functions including endocytosis. Their formation requires membrane proteins (caveolins) and cytoplasmic proteins (cavins), so that gene disruption of either caveolin-1 or cavin-1 (also known as PTRF, i.e., polymerase I and transcript release factor) results in caveola deficiency. Here we evaluated the ability of a 16 charged asymmetric arginine dendrimer to transfect plasmid DNA into cultured cells. We unveiled efficient transfection efficiencies (≥30%) 24-48 h after exposing the cells to dendrimer/pDNA complexes for only 5 min. Using wild type (WT) and caveolin-1 or PTRF gene-disrupted, i.e., caveola-deficient mouse embryo fibroblasts, we further show that caveolae promote pDNA transfection by 16 charged asymmetric arginine dendrimers.
基于不对称阳离子氨基酸的树枝状大分子是高度分支的化学合成基因载体，用于将诸如质粒DNA等物质运输穿过质膜。我们之前已经证明，它们倾向于进入形成小窝的细胞，这是由正电荷密度驱动并由精氨酸头部基团促进的。小窝是质膜亚结构域，具有包括内吞作用在内的多种细胞功能。它们的形成需要膜蛋白（小窝蛋白）和细胞质蛋白（窖蛋白），因此小窝蛋白-1或窖蛋白-1（也称为PTRF，即聚合酶I和转录释放因子）的基因破坏会导致小窝缺陷。在这里，我们评估了一种带16个电荷的不对称精氨酸树枝状大分子将质粒DNA转染到培养细胞中的能力。在将细胞暴露于树枝状大分子/质粒DNA复合物仅5分钟后，我们在24至48小时后发现了高效的转染效率（≥30%）。使用野生型（WT）以及小窝蛋白-1或PTRF基因破坏的，即小窝缺陷的小鼠胚胎成纤维细胞，我们进一步表明小窝促进了带16个电荷的不对称精氨酸树枝状大分子对质粒DNA的转染。
