title: Putrescine is required for the expression of eif-5a in Trichomonas vaginalis.
abstract: Recently, we found that Trichomonas vaginalis contains a eukaryotic translation initiation factor 5A (TveIF-5A) with unknown function in this parasite. eIF-5A is the only cellular protein dependent of polyamines to form a hypusine residue, an unusual basic amino acid that is post-translationally formed by modification of a single specific lysine residue in an eIF-5A precursor protein. The purpose of this study was to determine the effect of a putrescine analogue, 1,4-diamino-2-butanone (DAB), on tveif-5a mRNA and TveIF-5A protein expression. TveIF-5A protein expression was reduced by inhibition of putrescine biosynthesis, and tveif-5a mRNA levels were reduced ∼90%, as shown by western blot and immunofluorescence assays. Cycloheximide treatment reduced the amount of mature TveIF-5A protein at 4h and decreased the tveif-5a transcript level at 2h, according to western blot, RT-PCR and qRT-PCR analyses. Actinomycin D treatment showed that the tveif-5a mRNA had half-life of ∼2.5h in DAB-treated parasites. The half-life of tveif-5a mRNA was ∼4.5h under exogenous putrescine conditions. These results suggest that putrescine is required for tveif-5a mRNA stability, and it is necessary for the expression, stability and maturation of TveIF-5A protein.
authors.affiliation: Posgrado en Ciencias Genómicas, Universidad Autónoma de la Ciudad de México (UACM), San Lorenzo, Mexico City.
authors.forename: Bertha Isabel
authors.initials: BI
authors.lastname: Carvajal-Gamez
authors.forename: Rossana
authors.initials: R
authors.lastname: Arroyo
authors.forename: Minerva
authors.initials: M
authors.lastname: Camacho-Nuez
authors.forename: Rosalia
authors.initials: R
authors.lastname: Lira
authors.forename: Máximo
authors.initials: M
authors.lastname: Martínez-Benitez
authors.forename: María Elizbeth
authors.initials: ME
authors.lastname: Alvarez-Sánchez
mesh_terms: D005786:Gene Expression Regulation; D010448:Peptide Initiation Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D055550:Protein Stability; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011700:Putrescine / Q000096:biosynthesis*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D014246:Trichomonas vaginalis / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000097574:Eukaryotic Translation Initiation Factor 5A
chemical_list: D010448:Peptide Initiation Factors; D015800:Protozoan Proteins; D011700:Putrescine; D016601:RNA-Binding Proteins; D000097574:Eukaryotic Translation Initiation Factor 5A