Down-regulation of the CrHPT1 histidine phosphotransfer protein prevents cytokinin-mediated up-regulation of CrDXR, and CrG10H transcript levels in periwinkle cell cultures.
In Catharanthus roseus cell cultures, cytokinins (CK) improve monoterpenoid indole alkaloids (MIAs) accumulation. This metabolite production is correlated with an increase of transcripts corresponding to genes encoding both elements of the CK-signaling pathway and enzymes implicated in MIAs biosynthesis. However, it has not been demonstrated that the CK signal, leading to MIAs accumulation, comes through components identified as belonging to the CK-signaling pathway. In this work, we addressed this question, by transgenesis, using an inducible RNAi system targeting element of CK-signaling. In transgenic lines, the up-regulation by CK of two genes involved in MIA biosynthesis was abolished. These results demonstrate a relationship between the CK-signaling and the MIAs biosynthetic pathways.
EA 2106 Biomolécules et Biotechnologies Végétales, Faculté de Pharmacie, Université François Rabelais de Tours, 31 Avenue Monge, 37200 Tours, France.
Aniça
A
Amini
Françoise
F
Andreu
Gaëlle
G
Glévarec
Marc
M
Rideau
Joël
J
Crèche
D019747:Aldose-Ketose Isomerases / Q000235:genetics* / Q000378:metabolism; D030008:Catharanthus / Q000235:genetics* / Q000378:metabolism*; D018929:Cell Culture Techniques; D002460:Cell Line; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics* / Q000378:metabolism; D003583:Cytokinins / Q000378:metabolism*; D003907:Dexamethasone / Q000494:pharmacology; D015536:Down-Regulation; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D020868:Gene Silencing; D009097:Multienzyme Complexes / Q000235:genetics* / Q000378:metabolism; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D010770:Phosphotransferases / Q000235:genetics* / Q000378:metabolism; D034622:RNA Interference; D046948:Secologanin Tryptamine Alkaloids / Q000378:metabolism; D015398:Signal Transduction; D014158:Transcription, Genetic
D003583:Cytokinins; D009097:Multienzyme Complexes; D046948:Secologanin Tryptamine Alkaloids; D003907:Dexamethasone; D003577:Cytochrome P-450 Enzyme System; D010088:Oxidoreductases; C114231:1-deoxy-D-xylulose 5-phosphate reductoisomerase; C081675:geraniol 10-hydroxylase; D010770:Phosphotransferases; D019747:Aldose-Ketose Isomerases