A network of jasmonate-responsive bHLH factors modulate monoterpenoid indole alkaloid biosynthesis in Catharanthus roseus.
New Phytol
; 217(4): 1566-1581, 2018 03.
Article
en En
| MEDLINE
| ID: mdl-29178476
ABSTRACT
The pharmaceutically valuable monoterpene indole alkaloids (MIAs) in Catharanthus roseus are derived from the indole and iridoid pathways that respond to jasmonate (JA) signaling. Two classes of JA-responsive bHLH transcription factor (TF), CrMYC2 and BIS1/BIS2, are known to regulate the indole and iridoid pathways, respectively. However, upregulation of either one of the TF genes does not lead to increased MIA accumulation. Moreover, little is known about the interconnection between the CrMYC2 and BIS transcriptional cascades and the hierarchical position of BIS1/BIS2 in JA signaling. Here, we report that a newly identified bHLH factor, Repressor of MYC2 Targets 1 (RMT1), is activated by CrMYC2 and BIS1, and acts as a repressor of the CrMYC2 targets. In addition, we isolated and functionally characterized the core C. roseus JA signaling components, including CORONATINE INSENSITIVE 1 (COI1) and JASMONATE ZIM domain (JAZ) proteins. CrMYC2 and BIS1 are repressed by the JAZ proteins in the absence of JA, but de-repressed by the SCFCOI1 complex on perception of JA. Our findings suggest that the repressors, JAZs and RMT1, mediate crosstalk between the CrMYC2 and BIS regulatory cascades to balance the metabolic flux in MIA biosynthesis.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Ciclopentanos
/
Catharanthus
/
Alcaloides Indólicos
/
Monoterpenos
/
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico
/
Vías Biosintéticas
/
Redes Reguladoras de Genes
/
Oxilipinas
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
New Phytol
Asunto de la revista:
BOTANICA
Año:
2018
Tipo del documento:
Article
País de afiliación:
Estados Unidos