Asayama Shoichiro, Sudo Miyuki, Kawakami Hiroyoshi
Department of Applied Chemistry, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan.
Nucleic Acids Symp Ser (Oxf). 2009(53):253-4. doi: 10.1093/nass/nrp127.
The DNA ternary complexes with carboxymethyl poly(L-histidine) (CM-PLH) and poly(ethylenimine) (PEI) have released the DNA binary complexes with PEI by the protonation of CM-PLH at endosomal/lysosomal pH. The dissociation of the CM-PLH from the CM-PLH/PEI/DNA ternary complexes is proved by the fluorescence resonance energy transfer (FRET) analysis between the CM-PLH and PEI. The resulting PEI/DNA binary complexes easily released DNA, as compared with the CM-PLH/PEI/DNA ternary complexes, which was examined by competitive exchange with dextran sulfate. The release of the DNA binary complexes from the ternary complexes is promising mechanism for higher transfection activity by the CM-PLH/PEI/DNA ternary complexes.
与羧甲基聚（L-组氨酸）（CM-PLH）和聚乙烯亚胺（PEI）形成的DNA三元复合物，通过CM-PLH在内体/溶酶体pH值下的质子化作用，释放了与PEI形成的DNA二元复合物。CM-PLH与PEI之间的荧光共振能量转移（FRET）分析证明了CM-PLH从CM-PLH/PEI/DNA三元复合物中的解离。与CM-PLH/PEI/DNA三元复合物相比，所得的PEI/DNA二元复合物更容易释放DNA，这是通过与硫酸葡聚糖的竞争性交换来检测的。从三元复合物中释放DNA二元复合物是CM-PLH/PEI/DNA三元复合物具有更高转染活性的有前景的机制。
