The Company of Biologists, Journal of Cell Science, 2014
DOI: 10.1242/jcs.150573
Full text: Download
Host cell invasion by Trypanosoma cruzi shares mechanistic elements with plasma membrane injury and repair. Both processes require Ca2+-triggered exocytosis of lysosomes, exocytosis of acid sphingomyelinase, and formation of ceramide-enriched endocytic compartments. T. cruzi invades at peripheral sites, suggesting a need for spatial regulation of membrane traffic. Here we show that Exo70 and Sec8, components of the exocyst complex, accumulate in nascent T. cruzi vacuoles and at sites of mechanical wounding. Exo70 or Sec8 depletion inhibits T. cruzi invasion and Ca2+-dependent resealing of mechanical wounds, but does not affect repair of smaller lesions caused by pore-forming toxins. Thus, T. cruzi invasion and mechanical lesion repair share a unique requirement for the exocyst, consistent with a dependence on targeted membrane delivery.