Shiga toxin induces tubular membrane invaginations for its uptake into cells.
Nature. 2007-11-01; 450(7170): 670-675
DOI: 10.1038/nature05996
Read on PubMed
1. Nature. 2007 Nov 29;450(7170):670-5.
Shiga toxin induces tubular membrane invaginations for its uptake into cells.
Römer W(1), Berland L, Chambon V, Gaus K, Windschiegl B, Tenza D, Aly MR,
Fraisier V, Florent JC, Perrais D, Lamaze C, Raposo G, Steinem C, Sens P,
Bassereau P, Johannes L.
Author information:
(1)Institut Curie, Centre de Recherche, Laboratoire Trafic, Signalisation et
Ciblage Intracellulaires, Paris Cedex 05, France.
Clathrin seems to be dispensable for some endocytic processes and, in several
instances, no cytosolic coat protein complexes could be detected at sites of
membrane invagination. Hence, new principles must in these cases be invoked to
account for the mechanical force driving membrane shape changes. Here we show
that the Gb3 (glycolipid)-binding B-subunit of bacterial Shiga toxin induces
narrow tubular membrane invaginations in human and mouse cells and model
membranes. In cells, tubule occurrence increases on energy depletion and
inhibition of dynamin or actin functions. Our data thus demonstrate that active
cellular processes are needed for tubule scission rather than tubule formation.
We conclude that the B-subunit induces lipid reorganization that favours negative
membrane curvature, which drives the formation of inward membrane tubules. Our
findings support a model in which the lateral growth of B-subunit-Gb3
microdomains is limited by the invagination process, which itself is regulated by
membrane tension. The physical principles underlying this basic cargo-induced
membrane uptake may also be relevant to other internalization processes, creating
a rationale for conceptualizing the perplexing diversity of endocytic routes.
DOI: 10.1038/nature05996
PMID: 18046403 [Indexed for MEDLINE]