Protein delivery with transportans is mediated by caveolae rather than flotillin-dependent pathways
2009 (English)In: Bioconjugate chemistry, ISSN 1043-1802, E-ISSN 1520-4812, Vol. 20, no 5, 877-887 p.Article in journal (Refereed) Published
Delivery of large bioactive cargoes into cells with the help of cell-penetrating peptides (CPPs) is mostly based on endocytic processes. Here we map the cellular pathways used by transportan and transportan 10 (TP10) for protein transduction in HeLa cells. CPP-mediated cellular delivery is often suggested to be lipid-raft-dependent; therefore, we used flotillin-1, caveolin, Rab5, and PI3P as markers to elucidate the involvement of these particular endosomal pathways in the protein uptake process. Confocal laser scanning and electron microscopy reveal only a negligible overlap of avidin/neutravidin conveyed into cells by transportans with the raft marker flotillin-1 or early endosomal markers Rab5 and PI3P. However, about 20% of protein−CPP complexes colocalize with the caveolar/caveosomal marker caveolin, and down-regulation of caveolin-1 by siRNA treatment leads to the inhibition of the CPP-mediated protein uptake by 30−50%. On the contrary, the lack of flotillin-1 increases rather than decreases the CPP-mediated protein transport. The participation of the caveolin-1-dependent pathway in CPP-mediated protein delivery was also corroborated by using caveolin-1 knockout mouse embryonic fibroblasts.
Place, publisher, year, edition, pages
2009. Vol. 20, no 5, 877-887 p.
Research subject Neurochemistry with Molecular Neurobiology
IdentifiersURN: urn:nbn:se:su:diva-32178DOI: 10.1021/bc800416fISI: 000266292500006OAI: oai:DiVA.org:su-32178DiVA: diva2:279687