title: Cytokinin-auxin crosstalk in cell type specification.
abstract: Auxin and cytokinin affect cell fate specification transcriptionally and non-transcriptionally, and their roles have been characterised in several founder cell specification and activation contexts. Similarly to auxin, local cytokinin synthesis and response gradients are instructive, and the roles of ARABIDOPSIS RESPONSE REGULATOR 7/15 (ARR7/15) and the negative cytokinin response regulator ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEIN 6, as well as auxin signalling via MONOPTEROS/BODENLOS, are functionally conserved across different developmental processes. Auxin and cytokinin crosstalk is tissue- and context-specific, and may be synergistic in the shoot apical meristem (SAM) but antagonistic in the root. We review recent advances in understanding the interactions between auxin and cytokinin in pivotal developmental processes, and show that feedback complexity and the multistep nature of specification processes argue against a single morphogenetic signal.
authors: Institute of Developmental Biology, Cologne Biocenter, Zülpicher Strasse 47b, 50674 Cologne, Germany. Electronic address: John.chandler@uni-koeln.de.
authors: John William
authors: JW
authors: Chandler
authors: Institute of Developmental Biology, Cologne Biocenter, Zülpicher Strasse 47b, 50674 Cologne, Germany.
authors: Wolfgang
authors: W
authors: Werr
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism; D003583:Cytokinins / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: C470377:ARR15 protein, Arabidopsis; C507238:ARR7 protein, Arabidopsis; D029681:Arabidopsis Proteins; D003583:Cytokinins; D004268:DNA-Binding Proteins; D007210:Indoleacetic Acids; D014157:Transcription Factors
keywords: ARABIDOPSIS HISTIDINE PHOSPHOTRANSFER PROTEIN 6; ARR15; ARR7; MONOPTEROS/BODENLOS; auxin; crosstalk; cytokinin; founder cell specification