title: uORF, a regulatory mechanism of the Arabidopsis polyamine oxidase 2.
abstract: The translational efficiency of an mRNA can be modulated by elements located in the 5'-untranslated region. The flavin-containing polyamine oxidases catabolize oxidative deamination of spermidine and spermine, thus contributing to polyamine homeostasis as well as diverse biological processes through their reaction products. In this study, we characterized the uORF of AtPAO2 gene using the GUS reporter gene. Transgenic lines harboring the native AtPAO2 promoter or the constitutive CaMV 35S promoter show that the uORF negatively affects GUS expression. Exogenous applications of PAs positively modulate GUS expression, thus alleviating the negative effect of AtPAO2 uORF, while treatments with MGBG inhibitor show an opposite effect. Our data suggest that AtPAO2 uORF regulatory mechanism is modulated by polyamines. In addition, we present a comparative in silico study of the uORFs identified in several plant transcripts encoding polyamine oxidases in both mono- and dicotyledonous plants as well as in the Bryophyte Physcomitrella patens. The polyamine oxidase uORF-encoded peptides are conserved among families and share conserved features such as their position, length, and amino acid sequence. Our findings provide new insights into the regulatory mechanism of polyamine oxidase genes and encourage further exploration to assess the biological significance of uORFs in the polyamine catabolic pathway.
authors.affiliation: Division de Biologia Molecular, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa de San Jose 2055, AP 3-74 Tangamanga, 78216, San Luis Potosi, SLP, Mexico.
authors.forename: Maria L
authors.initials: ML
authors.lastname: Guerrero-González
authors.forename: Margarita
authors.initials: M
authors.lastname: Rodríguez-Kessler
authors.forename: Juan F
authors.initials: JF
authors.lastname: Jiménez-Bremont
mesh_terms: D020121:5' Untranslated Regions; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D017124:Conserved Sequence; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D023061:Gene Order; D008969:Molecular Sequence Data; D005810:Multigene Family; D016366:Open Reading Frames; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D011073:Polyamines / Q000378:metabolism / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics; D036226:Seedlings / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D014158:Transcription, Genetic; D000097667:Polyamine Oxidase
chemical_list: D020121:5' Untranslated Regions; D000587:Oxidoreductases Acting on CH-NH Group Donors; D011073:Polyamines; D012333:RNA, Messenger; D000097667:Polyamine Oxidase