Histidine-containing phosphotransfer domain extinction by RNA interference turns off a cytokinin signalling circuitry in Catharanthus roseus suspension cells.
We previously reported that cytokinins (CK) induce the fast and specific transcription of CrRR1, a gene encoding a type A response regulator in Catharanthus roseus cell cultures. Here, we characterized the CrHPt1 gene that encodes a histidine-containing phosphotransfer domain. CrHPt1 was silenced through RNA interference (RNAi) to test its possible implication in the CK signalling pathway. In transgenic lines stably transformed with an intron-spliced construct, the degradation of CrHPt1 transcripts abolishes the CK inductive effect on CrRR1 transcription. These result give a new in vivo functional argument for the crucial role of HPt proteins in the CK signalling pathway leading to the expression of the genes encoding type A response regulators. They also show that RNAi is a powerful strategy to turn off the CK signalling circuitry.
Papon
Nicolas
N
EA 2106, Plant Molecular Biology and Biochemistry Department, Faculty of Pharmacy, 31 avenue Monge, F-37200 Tours, France.
Vansiri
Amerin
A
Gantet
Pascal
P
Chénieux
Jean-Claude
JC
Rideau
Marc
M
Crèche
Joël
J
D030008:Catharanthus / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D003583:Cytokinins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000166:cytology; D020868:Gene Silencing; D017343:Genes, Plant; D006639:Histidine / Q000378:metabolism*; D018515:Plant Leaves / Q000166:cytology; D018547:Plant Stems / Q000166:cytology; D030821:Plants, Genetically Modified; D017434:Protein Structure, Tertiary; D034741:RNA, Small Interfering / Q000737:chemistry / Q000378:metabolism*; D015398:Signal Transduction
D003583:Cytokinins; D034741:RNA, Small Interfering; D006639:Histidine