title: Trypanosoma cruzi: modulation of HSP70 mRNA stability by untranslated regions during heat shock.
abstract: Gene regulation in trypanosomatids occurs mainly by post-transcriptional mechanisms modulating mRNA stability and translation. We have investigated heat shock protein (HSP) 70 gene regulation in Trypanosoma cruzi, the causal agent of Chagas' disease. The HSP70 mRNA's half-life increases after heat shock, and the stabilization is dependent on protein synthesis. In a cell-free RNA decay assay, a U-rich region in the 3' untranslated region (UTR) is a target for degradation, which is reduced when in the presence of protein extracts from heat shocked cells. In a transfected reporter gene assay, both the 5'- and 3'-UTRs confer temperature-dependent regulation. Both UTRs must be present to increase mRNA stability at 37 degrees C, indicating that the 5'- and 3'-UTRs act cooperatively to stabilize HSP70 mRNA during heat shock. We conclude that HSP70 5'- and 3'-UTRs regulate mRNA stability during heat shock in T. cruzi.
authors.affiliation: Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Deivid C
authors.initials: DC
authors.lastname: Rodrigues
authors.forename: Rosane
authors.initials: R
authors.lastname: Silva
authors.forename: Edson
authors.initials: E
authors.lastname: Rondinelli
authors.forename: Turán P
authors.initials: TP
authors.lastname: Urményi
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics / Q000502:physiology*; D020121:5' Untranslated Regions / Q000235:genetics / Q000502:physiology*; D001483:Base Sequence; D015152:Blotting, Northern; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics / Q000378:metabolism; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000502:physiology*; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D006207:Half-Life; D006358:Hot Temperature; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection; D014349:Trypanosoma cruzi / Q000235:genetics* / Q000378:metabolism
chemical_list: D020413:3' Untranslated Regions; D020121:5' Untranslated Regions; D016054:DNA, Protozoan; D018840:HSP70 Heat-Shock Proteins; D012333:RNA, Messenger; D015500:Chloramphenicol O-Acetyltransferase