Physiology and molecular genetics of multidrug resistance in Entamoeba histolytica.
Entamoeba histolytica presents the evolutionarily conserved multidrug-resistance (MDR) phenotype, discovered in mammalian cells. MDR cells overexpress the membrane P-glycoprotein, which excludes unrelated drugs from the cytoplasm. E. histolytica mutants exhibit cross-resistance to unrelated drugs, which are pumped out from the cytoplasm. In drug-resistant trophozoites, the constitutively expressed EhPg1 gene appears to be up-regulated by a C/EBP-like factor and a multiprotein complex that were not found in drug-sensitive trophozoites. The drug-induced EhPgp5 gene, on the other hand, appears to be up-regulated by AP-1 and HOX factors. Here we review the main physiological and molecular facts of the MDR phenotype in E. histolytica. Copyright 1999 Harcourt Publishers Ltd.
Orozco
Esther
E
Department of Experimental Pathology, Program of Molecular Biomedicine, CINVESTAV-IPN, CICATA-IPN, A.P 14-740, México, D.F., 
Gómez
Consuelo
C
Pérez
D. Guillermo
DG