Tag Archives: statistics

New publication: AtMYB93 is a novel negative regulator of lateral root development in Arabidopsis

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Thanks to Juliet Coates, we have a new publication:

Gibbs, D. J., Voß, U., Harding, S. A., Fannon, J., Moody, L. A., Yamada, E., Swarup, K., Nibau, C., Bassel, G. W., Choudhary, A., Lavenus, J., Bradshaw, S. J., Stekel, D. J., Bennett, M. J. and Coates, J. C. 2014. AtMYB93 is a novel negative regulator of lateral root development in Arabidopsis. New Phytologist. doi: 10.1111/nph.12879.

Summary

  • Plant root system plasticity is critical for survival in changing environmental conditions. One important aspect of root architecture is lateral root development, a complex process regulated by hormone, environmental and protein signalling pathways.
  • Here we show, using molecular genetic approaches, that the MYB transcription factor AtMYB93 is a novel negative regulator of lateral root development in Arabidopsis.
  • We identify AtMYB93 as an interaction partner of the lateral-root-promoting ARABIDILLO proteins. Atmyb93 mutants have faster lateral root developmental progression and enhanced lateral root densities, while AtMYB93-overexpressing lines display the opposite phenotype. AtMYB93 is expressed strongly, specifically and transiently in the endodermal cells overlying early lateral root primordia and is additionally induced by auxin in the basal meristem of the primary root. Furthermore, Atmyb93 mutant lateral root development is insensitive to auxin, indicating that AtMYB93 is required for normal auxin responses during lateral root development.
  • We propose that AtMYB93 is part of a novel auxin-induced negative feedback loop stimulated in a select few endodermal cells early during lateral root development, ensuring that lateral roots only develop when absolutely required. Putative AtMYB93 homologues are detected throughout flowering plants and represent promising targets for manipulating root systems in diverse crop species.

And it has even made BBSRC headlines.

To be fair, most credit goes to Juliet and to Dan Gibbs, who have been working on this project for many years. My contribution is fairly minor: I am responsible for the p-values in the manuscript! One of the referees was unhappy that some of the claims lacked statistical backing (which is fair enough – I would have made the same point as a referee) so I ran some likelihood ratio tests with simulated data in order to ensure that all claims had statistical backing. I’m really pleased for Juliet and Dan, because I know how much they have put into this paper.