title: Characterization of chaperonin 10 (Cpn10) from the intestinal human pathogen Entamoeba histolytica.
abstract: Entamoeba histolytica is the causative agent of amoebiasis, a poverty-related disease that kills an estimated 100 000 people each year. E. histolytica does not contain "standard mitochondria", but harbours mitochondrial remnant organelles called mitosomes. These organelles are characterized by the presence of mitochondrial chaperonin Cpn60, but little else is known about the functions and molecular composition of mitosomes. In this study, a gene encoding molecular chaperonin Cpn10--the functional partner of Cpn60--was cloned, and its structure and expression were characterized, as well as the cellular localization of its encoded protein. The 5' untranslated region of the gene contains all of the structural promoter elements required for transcription in this organism. The amoebic Cpn10, like Cpn60, is not significantly upregulated upon heat-shock treatment. Computer-assisted protein modelling, and specific antibodies against Cpn10 and Cpn60, suggest that both proteins interact with each other, and that they function in the same intracellular compartment. Thus, E. histolytica appears to have retained at least two of the key molecular components required for the refolding of imported mitosomal proteins.
authors.affiliation: School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: van der Giezen
authors.affiliation: School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK.
authors.forename: Gloria
authors.initials: G
authors.lastname: León-Avila
authors.affiliation: School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK.
authors.forename: Jorge
authors.initials: J
authors.lastname: Tovar
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D018835:Chaperonin 10 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016054:DNA, Protozoan / Q000032:analysis; D004748:Entamoeba histolytica / Q000235:genetics / Q000378:metabolism*; D018869:Heat-Shock Response; D006801:Humans; D007422:Intestines / Q000469:parasitology*; D008969:Molecular Sequence Data; D010802:Phylogeny
chemical_list: D018835:Chaperonin 10; D016054:DNA, Protozoan