Muerte celular similar a apoptosis en leishmania spp.una aproximación a su regulación

Abstract

The relevance of programmed cell death (PCD) on Leishmania parasites has been a controversial issue during the last ten years. Some recent evidences suggest that the apoptotic-like death showed by this organism may be essential for the establishment and maintenance of its pathogenic behavior and for survival in to the vertebrate host. Although several putative effectors molecules such as EndoG and metacaspases have been identified and characterized, knowledge about Leishmania PCD is still far to be completed. The role of the single mitochondrion and that of specific molecules involved in regulation of this pathway are important issues yet to be clarified. Apoptosis is classically regulated by the Bcl-2 family of proteins; however, recently the Bax Inhibitor-1 protein (BI-1) and other molecules like peptidases have been as well involved in the process. Since conventional strategies to identify apoptosis-like regulatory proteins in protozoan parasites have failed, we have used proteomic and genomic strategies to search for this kind of molecules in Leishmania parasites. Here we describe the identification of 6 proteins that are potentially involved in the apoptosis-like cell death regulation in Leishmania. In four of them we have been able to demonstrate changes in the death process as a consequence of its over-expression. Thus, those proteins can be included in the very small group of molecules involved in cell death regulation in protozoan parasites.