Henriques Sónia T, Costa Júlia, Castanho Miguel A R B
Centro de Química e Bioquímica, Faculdade de Ciências da Universidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisboa, Portugal.
FEBS Lett. 2005 Aug 15;579(20):4498-502. doi: 10.1016/j.febslet.2005.06.085.
Cell-penetrating peptides (CPPs) are able to translocate across biological membranes and deliver bioactive proteins. Cellular uptake and intracellular distribution of CPPs is commonly evaluated with fluorescent labels, which can alter peptide properties. The effect of carboxyfluorescein label in the Lys-rich domain of the amphipathic CPP pep-1, was evaluated and compared with non-labelled pep-1 in vitro and in vivo. A reduced membrane affinity and an endosomal-dependent translocation mechanism, at variance with non-labelled pep-1, were detected. Therefore, the charged domain is not a mere enabler of peptide adsorption but has a crucial role in the translocation pathway of non-labelled pep-1.
细胞穿透肽（CPPs）能够跨生物膜转运并递送生物活性蛋白。CPPs的细胞摄取和细胞内分布通常用荧光标记物进行评估，而荧光标记物会改变肽的性质。评估了两亲性CPP pep-1富含赖氨酸结构域中羧基荧光素标记的影响，并在体外和体内将其与未标记的pep-1进行比较。检测到其膜亲和力降低以及内体依赖性转运机制，这与未标记的pep-1不同。因此，带电荷结构域不仅是肽吸附的促成因素，而且在未标记pep-1的转运途径中起关键作用。
