Detergent-resistant membranes are platforms for actinoporin pore-forming activity on intact cells |
| |
Authors: | Alegre-Cebollada Jorge Rodríguez-Crespo Ignacio Gavilanes José G del Pozo Alvaro Martínez |
| |
Institution: | Departamento de Bioquímica, Facultad de Química, Universidad Complutense, Madrid, Spain. |
| |
Abstract: | Sticholysin II is a pore-forming toxin produced by the sea anemone Stichodactyla helianthus. We studied its cytolytic activity on COS-7 cells. Fluorescence spectroscopy and flow cytometry revealed that the toxin permeabilizes cells to propidium cations in a dose-dependent and time-dependent manner. This permeabilization is impaired by preincubation of cells with cyclodextrin. Isolation of detergent-resistant cellular membranes showed that sticholysin II colocalizes with caveolin-1 in fractions corresponding to raft-like domains. The interaction of sticholysin II with such domains is only lipid dependent as it also occurs in the absence of any other membrane-associated protein. Toxin binding to raft-like lipid vesicles inhibited cell permeabilization. The results suggest that sticholysin II promotes pore formation in COS-7 cells through interaction with membrane domains which behave like cellular rafts. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|