Proteasome activity is required for the stage-specific transformation of a protozoan parasite.

• DOI: 10.1084/jem.184.5.1909
• Publication Date: 2004-06-24T07:56:10Z
• Authors: J González; F J Ramalho-Pinto; U Frevert; J Ghiso; S Tomlinson; J Scharfstein; E J Corey; V Nussenzweig
• Keywords: Lactacystin; Amastigote

A prominent feature of the life cycle intracellular parasites is profound morphological changes they undergo during development in vertebrate and invertebrate hosts. In eukaryotic cells, most cytoplasmic proteins are degraded proteasomes. Here, we show that transformation axenic medium trypomastigotes Trypanosoma cruzi into amastigote-like organisms, parasite from amastigotes trypomastigotes, prevented by lactacystin, or a peptide aldehyde inhibits proteasome function. Clasto-lactacystin, an inactive analogue cell-permeant inhibitors T. cysteine proteinases have no effect. We also identified 20S proteasomes as target lactacystin vivo. Our results document essential role stage-specific protozoan.