Cargando…
Inhibition of caveolar uptake, SV40 infection, and β1-integrin signaling by a nonnatural glycosphingolipid stereoisomer
Caveolar endocytosis is an important mechanism for the uptake of certain pathogens and toxins and also plays a role in the internalization of some plasma membrane (PM) lipids and proteins. However, the regulation of caveolar endocytosis is not well understood. We previously demonstrated that caveola...
Autores principales: | , , , , , , , |
---|---|
Formato: | Texto |
Lenguaje: | English |
Publicado: |
The Rockefeller University Press
2007
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2064075/ https://www.ncbi.nlm.nih.gov/pubmed/17371832 http://dx.doi.org/10.1083/jcb.200609149 |
Sumario: | Caveolar endocytosis is an important mechanism for the uptake of certain pathogens and toxins and also plays a role in the internalization of some plasma membrane (PM) lipids and proteins. However, the regulation of caveolar endocytosis is not well understood. We previously demonstrated that caveolar endocytosis and β1-integrin signaling are stimulated by exogenous glycosphingolipids (GSLs). In this study, we show that a synthetic GSL with nonnatural stereochemistry, β-d-lactosyl-N-octanoyl-l-threo-sphingosine, (1) selectively inhibits caveolar endocytosis and SV40 virus infection, (2) blocks the clustering of lipids and proteins into GSLs and cholesterol-enriched microdomains (rafts) at the PM, and (3) inhibits β1-integrin activation and downstream signaling. Finally, we show that small interfering RNA knockdown of β1 integrin in human skin fibroblasts blocks caveolar endocytosis and the stimulation of signaling by a GSL with natural stereochemistry. These experiments identify a new compound that can interfere with biological processes by inhibiting microdomain formation and also identify β1 integrin as a potential mediator of signaling by GSLs. |
---|