title: Intraerythrocytic polyubiquitin expression in Plasmodium falciparum is subjected to developmental and heat-shock control.
abstract: The polyubiquitin gene of the human protozoan parasite Plasmodium falciparum (PfpUB) was cloned and shown to be comprised of five tandem repeats of the ubiquitin open reading frame, present as a single copy on chromosome 12. The 1672 bp of PfpUB is interrupted at the 5' end by a single intron of 526 bp. PfpUB expression is developmentally regulated in intraerythrocytic stages with a marked increase in both steady-state transcript and polyubiquitin protein levels in late trophozoite stages. On response to heat shock, late stage parasites (late trophozoites and schizonts) have a slightly elevated PfpUB transcript level as well as readily observable increases in the amount of polyubiquitin and ubiquitin-conjugated proteins.
authors.affiliation: Institute of Molecular Medicine, Nuffield Department of Medicine, University of Oxford, UK. horrocks@hammer.imm.ox.ac.uk
authors.forename: P
authors.initials: P
authors.lastname: Horrocks
authors.forename: C I
authors.initials: CI
authors.lastname: Newbold
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001704:Biopolymers / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D015152:Blotting, Northern; D003001:Cloning, Molecular; D016054:DNA, Protozoan; D004912:Erythrocytes / Q000469:parasitology*; D019143:Evolution, Molecular; D005786:Gene Expression Regulation; D018869:Heat-Shock Response; D006801:Humans; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010963:Plasmodium falciparum / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D025821:Polyubiquitin; D017422:Sequence Analysis, DNA; D020080:Tandem Repeat Sequences / Q000235:genetics; D014158:Transcription, Genetic; D014452:Ubiquitins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D001704:Biopolymers; D016054:DNA, Protozoan; D014452:Ubiquitins; D025821:Polyubiquitin