A novel bHLH gene responsive to low nitrogen positively regulates the biosynthesis of medicinal tropane alkaloids in Atropa belladonna.
Int J Biol Macromol
; 266(Pt 1): 131012, 2024 May.
Article
em En
| MEDLINE
| ID: mdl-38522709
ABSTRACT
Medicinal tropane alkaloids (TAs), including hyoscyamine, anisodamine and scopolamine, are essential anticholinergic drugs specifically produced in several solanaceous plants. Atropa belladonna is one of the most important medicinal plants that produces TAs. Therefore, it is necessary to cultivate new A. belladonna germplasm with the high content of TAs. Here, we found that the levels of TAs were elevated under low nitrogen (LN) condition, and identified a LN-responsive bHLH transcription factor (TF) of A. belladonna (named LNIR) regulating the biosynthesis of TAs. The expression level of LNIR was highest in secondary roots where TAs are synthesized specifically, and was significantly induced by LN. Further research revealed that LNIR directly activated the transcription of hyoscyamine 6ß-hydroxylase gene (H6H) by binding to its promoter, which converts hyoscyamine into anisodamine and subsequently epoxidizes anisodamine to form scopolamine. Overexpression of LNIR upregulated the expression levels of TA biosynthesis genes and consequently led to the increased production of TAs. In summary, we functionally identified a LN-responsive bHLH gene that facilitated the development of A. belladonna with high-yield TAs under the decreased usage of nitrogen fertilizer.
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Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Tropanos
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Atropa belladonna
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Regulação da Expressão Gênica de Plantas
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Fatores de Transcrição Hélice-Alça-Hélice Básicos
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Oxigenases de Função Mista
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Nitrogênio
Idioma:
En
Revista:
Int J Biol Macromol
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
China