title: Expression and processing of megasome cysteine proteinases during Leishmania amazonensis differentiation.
abstract: Amastigotes of Leishmania species belonging to the Leishmania mexicana complex exhibit large lysosomes, called megasomes, which are rich in cysteine proteinases. Various aspects of the host-parasite interaction, the differentiation process as well as intracellular survival, have been attributed to these proteinases. The in vitro differentiation from promastigote to amastigote forms of Leishmania amazonensis was evaluated using the analysis of the expression of cysteine proteinase (Lpcys2) by Northern blot, Western blot and enzymatic activity. As promastigotes transformed to amastigotes, there was an increase in Lpcys2 RNA transcription, as well as an increase in Lpcys2 production and activity. Moreover, the processing rate of the cysteine proteinase precursor forms was also increased in amastigote forms. These results are in agreement with our previous study in which megasome development was demonstrated by morphometric and immunochemical analysis.
authors: Laboratório de Ultra-estrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. wsouza@biof.ufrj.br
authors: Tânia
authors: T
authors: Ueda-Nakamura
authors: Maria
authors: M
authors: da Conceição Rocha Sampaio
authors: Narcisa L
authors: NL
authors: Cunha-e-Silva
authors: Yara M
authors: YM
authors: Traub-Cseko
authors: Wanderley
authors: W
authors: de Souza
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D003546:Cysteine Endopeptidases / Q000096:biosynthesis* / Q000235:genetics; D066298:In Vitro Techniques; D007891:Leishmania / Q000201:enzymology* / Q000254:growth & development / Q000648:ultrastructure; D008247:Lysosomes / Q000201:enzymology* / Q000648:ultrastructure; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D003546:Cysteine Endopeptidases