Genetic approach towards the identification of auxin - cytokinin crosstalk components involved in root development

Department of Plant Systems Biology, VIB, Technologiepark 927, 9052 Ghent, Belgium.
Philosophical Transactions of The Royal Society B Biological Sciences (Impact Factor: 7.06). 06/2012; 367(1595):1469-78. DOI: 10.1098/rstb.2011.0233
Source: PubMed


Phytohormones are important plant growth regulators that control many developmental processes, such as cell division, cell differentiation, organogenesis and morphogenesis. They regulate a multitude of apparently unrelated physiological processes, often with overlapping roles, and they mutually modulate their effects. These features imply important synergistic and antagonistic interactions between the various plant hormones. Auxin and cytokinin are central hormones involved in the regulation of plant growth and development, including processes determining root architecture, such as root pole establishment during early embryogenesis, root meristem maintenance and lateral root organogenesis. Thus, to control root development both pathways put special demands on the mechanisms that balance their activities and mediate their interactions. Here, we summarize recent knowledge on the role of auxin and cytokinin in the regulation of root architecture with special focus on lateral root organogenesis, discuss the latest findings on the molecular mechanisms of their interactions, and present forward genetic screen as a tool to identify novel molecular components of the auxin and cytokinin crosstalk.

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Available from: Peter Marhavy, Mar 19, 2015
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    • "The root-apex TZ is a critical site for the perception and response to both endogenous phytohormones and environmental cues (Baluška et al., 2010), particularly to auxin, the key regulator of root development (Benková and Hejátko, 2009; Overvoorde et al., 2010; Bielach et al., 2012; Jansen et al., 2012; Lavenus et al., 2013). In conjunction with auxin, ethylene is also involved in the regulation of root growth (R uzicka et al., 2007; Swarup et al., 2007). "
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    • "Auxin–cytokinin crosstalk in root development CK–auxin antagonistic interactions in controlling root development is well known (Dello Ioio et al. 2008; Bielach et al. 2012). In A. thaliana, it has been demonstrated that CK promotes cell differentiation, repressing both auxin transport and signaling. "
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    Philosophical Transactions of The Royal Society B Biological Sciences 06/2012; 367(1595):1441-52. DOI:10.1098/rstb.2011.0234 · 7.06 Impact Factor
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