Local Auxin Biosynthesis Is a Key Regulator of Plant Development

• Published in: Developmental cell Vol. 47; no. 3; pp. 306 - 318.e5
• Main Authors: Brumos, Javier, Robles, Linda M., Yun, Jeonga, Vu, Thien C., Jackson, Savannah, Alonso, Jose M., Stepanova, Anna N.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 05.11.2018
• Subjects: Arabidopsis - metabolism; Arabidopsis Proteins - metabolism; auxin maxima; Biological Transport; ethylene response; Ethylenes - metabolism; flower fertility; Flowers - metabolism; Gene Expression Regulation, Plant - genetics; Indoleacetic Acids - metabolism; local auxin biosynthesis; Meristem - embryology; Meristem - metabolism; Morphogenesis; morphogenic gradient; Oxygenases; plant development; Plant Development - genetics; Plant Growth Regulators - genetics; Plant Growth Regulators - metabolism; Plant Roots - embryology; Plant Roots - genetics; Plant Roots - metabolism; polar auxin transport; root meristem; Spatio-Temporal Analysis; plant development; local auxin biosynthesis; ethylene response; auxin maxima; polar auxin transport; flower fertility; morphogenic gradient; root meristem
• ISSN: 1534-5807; 1878-1551; 1878-1551
• DOI: 10.1016/j.devcel.2018.09.022

Auxin is a major phytohormone that controls numerous aspects of plant development and coordinates plant responses to the environment. Morphogenic gradients of auxin govern cell fate decisions and underlie plant phenotypic plasticity. Polar auxin transport plays a central role in auxin maxima generation. The discovery of the exquisite spatiotemporal expression patterns of auxin biosynthesis genes of the WEI8/TAR and YUC families suggested that local auxin production may contribute to the formation of auxin maxima. Herein, we systematically addressed the role of local auxin biosynthesis in plant development and responses to the stress phytohormone ethylene by manipulating spatiotemporal patterns of WEI8. Our study revealed that local auxin biosynthesis and transport act synergistically and are individually dispensable for root meristem maintenance. In contrast, flower fertility and root responses to ethylene require local auxin production that cannot be fully compensated for by transport in the generation of morphogenic auxin maxima. [Display omitted] •Local auxin production in roots is required for maintaining functional root meristems•Local biosynthesis and transport of auxin cooperate at generating robust auxin maxima•Auxin produced in the root quiescent center is sufficient for root meristem viability The plant hormone auxin is a key regulator of plant growth and development. Brumos et al. show that local biosynthesis and polar transport of auxin act in concert to produce robust auxin maxima in the root quiescent center to sustain the meristematic potential of the root stem cell niche.