AtMYB93 is a novel negative regulator of lateral root development in Arabidopsis. Issue 4 (6th June 2014)

• Record Type: Journal Article
• Authors: Gibbs, Daniel J.; Voß, Ute; Harding, Susan A.; Fannon, Jessica; Moody, Laura A.; Yamada, Erika; Swarup, Kamal; Nibau, Candida; Bassel, George W.; Choudhary, Anushree; Lavenus, Julien; Bradshaw, Susan J.; Stekel, Dov J.; Bennett, Malcolm J.; Coates, Juliet C.
• Is Part Of: New phytologist. Volume 203:Issue 4(2014)
• Page Start: 1194
• Page End: 1207
• Publication Date: 2014-06-06
• Subjects: Botany -- Periodicals; 580
• DOI: 10.1111/nph.12879
• Languages: English
• ISSNs: 0028-646X

Abstract

<abstract abstract-type="main" id="nph12879-abs-0001"> <title>Summary</title> <p> <list id="nph12879-list-0001" list-type="bullet"> <list-item> <p>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.</p> </list-item> <list-item> <p>Here we show, using molecular genetic approaches, that the MYB transcription factor <italic>At</italic>MYB93 is a novel negative regulator of lateral root development in Arabidopsis.</p> </list-item> <list-item> <p>We identify <italic>At</italic>MYB93 as an interaction partner of the lateral‐root‐promoting ARABIDILLO proteins. <italic>Atmyb93</italic> mutants have faster lateral root developmental progression and enhanced lateral root densities, while <italic>At</italic>MYB93‐overexpressing lines display the opposite phenotype. <italic>AtMYB93</italic> 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, <italic>Atmyb93</italic> mutant lateral root development is insensitive to auxin, indicating that <italic>At</italic>MYB93 is required for normal auxin responses during lateral root development.</p> </list-item> <list-item> <p>We propose that <italic>At</italic>MYB93 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 <italic>At</italic>MYB93 homologues are detected throughout flowering plants and represent promising targets for manipulating root systems in diverse crop species.</p> </list-item> </list> </p> </abstract>