Molecular evolution of N-methylputrescine oxidase in tobacco.
Plant Cell Physiol
; 55(2): 436-44, 2014 Feb.
Article
en En
| MEDLINE
| ID: mdl-24287136
ABSTRACT
Biosynthesis of nicotine in tobacco requires N-methylputrescine oxidase (MPO), which belongs to the copper-containing amine oxidase superfamily. Previous studies identified tobacco MPO1 and its close homolog NtDAO1 (formerly called MPO2), of which MPO1 has been shown preferentially to oxidize N-methylated amines. We show here that NtDAO1, as well as a homologous Arabidopsis diamine oxidase (DAO), accept non-N-methylated amines more efficiently than their corresponding N-methylated amines. MPO1 is coordinately regulated with other nicotine biosynthesis genes with regard to COI1-MYC2-dependent jasmonate induction and its dependence on nicotine-specific ERF transcription factors, whereas NtDAO1 is constitutively expressed at low basal levels in tobacco plants. Both MPO1 and NtDAO1 are targeted to peroxisomes by their C-terminal motifs, and the peroxisomal localization of MPO1 is required for it to function in nicotine biosynthesis in jasmonate-elicited cultured tobacco cells. Restricted occurrence of the MPO subfamily in Nicotiana and Solanum indicates that, during the formation of the Solanaceae, MPO has evolved from a DAO, which functions in polyamine catabolism within peroxisomes, by optimizing substrate preference and gene expression patterns to be suitable for alkaloid formation.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Nicotiana
/
Putrescina
/
Amina Oxidasa (conteniendo Cobre)
/
Arabidopsis
/
Regulación de la Expresión Génica de las Plantas
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Plant Cell Physiol
Asunto de la revista:
BOTANICA
Año:
2014
Tipo del documento:
Article