TY - JOUR
T1 - Calpain-like
T2 - A Ca2+ dependent cystein protease in Entamoeba histolytica cell death
AU - Monroy, Virginia Sánchez
AU - Flores, Olivia Medel
AU - García, Consuelo Gómez
AU - Maya, Yesenia Chávez
AU - Fernández, Tania Domínguez
AU - Pérez Ishiwara, D. Guillermo
N1 - Publisher Copyright:
© 2015 Elsevier Inc.
PY - 2015/12/1
Y1 - 2015/12/1
N2 - Entamoeba histolytica programmed cell death (PCD) induced by G418 is characterized by the release of important amounts of intracellular calcium from reservoirs. Nevertheless, no typical caspases have been detected in the parasite, the PCD phenotype is inhibited by the cysteine protease inhibitor E-64. These results strongly suggest that Ca2+-dependent proteases could be involved in PCD. In this study, we evaluate the expression and activity of a specific dependent Ca2+ protease, the calpain-like protease, by real-time quantitative PCR (RTq-PCR), Western blot assays and a enzymatic method during the induction of PCD by G418. Alternatively, using cell viability and TUNEL assays, we also demonstrated that the Z-Leu-Leu-Leu-al calpain inhibitor reduced the rate of cell death. The results demonstrated 4.9-fold overexpression of calpain-like gene 1.5 h after G418 PCD induction, while calpain-like protein increased almost two-fold with respect to basal calpain-like expression after 3 h of induction, and calpain activity was found to be approximately three-fold higher 6 h after treatment compared with untreated trophozoites. Taken together, these results suggest that this Ca2+-dependent protease could be involved in the executory phase of PCD.
AB - Entamoeba histolytica programmed cell death (PCD) induced by G418 is characterized by the release of important amounts of intracellular calcium from reservoirs. Nevertheless, no typical caspases have been detected in the parasite, the PCD phenotype is inhibited by the cysteine protease inhibitor E-64. These results strongly suggest that Ca2+-dependent proteases could be involved in PCD. In this study, we evaluate the expression and activity of a specific dependent Ca2+ protease, the calpain-like protease, by real-time quantitative PCR (RTq-PCR), Western blot assays and a enzymatic method during the induction of PCD by G418. Alternatively, using cell viability and TUNEL assays, we also demonstrated that the Z-Leu-Leu-Leu-al calpain inhibitor reduced the rate of cell death. The results demonstrated 4.9-fold overexpression of calpain-like gene 1.5 h after G418 PCD induction, while calpain-like protein increased almost two-fold with respect to basal calpain-like expression after 3 h of induction, and calpain activity was found to be approximately three-fold higher 6 h after treatment compared with untreated trophozoites. Taken together, these results suggest that this Ca2+-dependent protease could be involved in the executory phase of PCD.
KW - Calpain-like
KW - Entamoeba histolytica
KW - G418
KW - PCD
UR - http://www.scopus.com/inward/record.url?scp=84951019877&partnerID=8YFLogxK
U2 - 10.1016/j.exppara.2015.10.005
DO - 10.1016/j.exppara.2015.10.005
M3 - Artículo
C2 - 26496790
SN - 0014-4894
VL - 159
SP - 245
EP - 251
JO - Experimental Parasitology
JF - Experimental Parasitology
ER -