Department of Chemistry and Biochemistry, The Ohio State University, 484 West 12th Avenue, Columbus, Ohio 43210, United States.
J Am Chem Soc. 2024 Sep 11;146(36):25371-25382. doi: 10.1021/jacs.4c10533. Epub 2024 Sep 2.
Cell-penetrating peptides (CPPs) enter the cell by two different mechanisms-endocytosis followed by endosomal escape and direct translocation at the plasma membrane. The mechanism of direct translocation remains unresolved. In this work, the direct translocation of nonaarginine (R9) and two cyclic CPPs (CPP12 and CPP17) into Jurkat cells was monitored by time-lapse confocal microscopy. Our results provide direct evidence that all three CPPs translocate across the plasma membrane by a recently discovered vesicle budding-and-collapse (VBC) mechanism. Membrane translocation is preceded by the formation of nucleation zones. Up to four different types of nucleation zones and three variations of the VBC mechanism were observed. The VBC mechanism reconciles the enigmatic and conflicting observations in the literature.
细胞穿透肽（CPPs）通过两种不同的机制进入细胞——内吞作用，随后是内涵体逃逸，以及在质膜处的直接转位。直接转位的机制仍未解决。在这项工作中，通过延时共聚焦显微镜监测了非精氨酸（R9）和两种环状 CPP（CPP12 和 CPP17）进入 Jurkat 细胞的直接转位。我们的结果提供了直接的证据，证明这三种 CPP 都通过最近发现的囊泡出芽和塌陷（VBC）机制穿过质膜。膜转位之前先形成成核区。观察到多达四种不同类型的成核区和三种 VBC 机制的变化。VBC 机制解释了文献中那些神秘且相互矛盾的观察结果。
