The trichomonad cysteine proteinase TVCP4 transcript contains an iron-responsive element

• Published in: FEBS letters 2007-06, Vol.581 (16), p.2919-2928
• Main Authors: Solano-González, Eduardo, Burrola-Barraza, Eduviges, León-Sicairos, Claudia, Avila-González, Leticia, Gutiérrez-Escolano, Lorena, Ortega-López, Jaime, Arroyo, Rossana
• Format: Article
• Language: English
• Subjects: Animals; Base Sequence; Cathepsin L; Cathepsins - genetics; CPs; Cysteine Endopeptidases - chemistry; Cysteine Endopeptidases - genetics; Cysteine proteinases; Enzyme Precursors - genetics; HeLa Cells; hIRP-1; human ferritin IRE sequence; human iron regulatory protein 1; Humans; IRE; IRE-fer; Iron - analysis; Iron - metabolism; Iron regulation; Iron Regulatory Protein 1 - metabolism; iron-responsive element; Iron-responsive element/iron regulatory protein system; Iron-responsive elements; Models, Biological; Molecular Sequence Data; Nucleic Acid Conformation; open reading frame; ORF; Post-transcriptional regulation; Recombinant Proteins - metabolism; Response Elements; RNA, Messenger - chemistry; RNA-binding proteins; RNA-Binding Proteins - metabolism; RNA–protein complexes; RPCs; SDS–PAGE; sodium dodecyl sulfate–polyacrylamide gel electrophoresis; Trichomonas vaginalis; Trichomonas vaginalis - chemistry; Trichomonas vaginalis - enzymology; Trichomonas vaginalis - genetics; Trichomonas vaginalis cysteine proteinase 4 gene; trypticase-yeast extract maltose; tvcp4; TYM; UNAM; Universidad Nacional Autónoma de México; untranslated regions; UTR's
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/j.febslet.2007.05.056

The differential expression of the Trichomonas vaginalis cysteine proteinase TVCP4 by iron at the protein synthesis level and the prediction of an iron-responsive element (IRE)-like stem-loop structure at the 5′-region of the T. vaginalis cysteine proteinase 4 gene ( tvcp4) mRNA suggest a post-transcriptional mechanism of iron regulation in trichomonads mediated by an IRE/IRP-like system. Gel-shifting, UV cross-linking and competition experiments demonstrated that this IRE-like structure specifically bound to human iron regulatory protein-1. IRP-like cytoplasmic proteins that bound human ferritin IRE sequence transcripts at low-iron conditions were also found in trichomonads. Thus, a post-transcriptional regulatory mechanism by iron for tvcp4 mediated by IRE/IRP-like interactions was found.