S1 basic leucine zipper transcription factors shape plant architecture by controlling C/N partitioning to apical and lateral organs

• 成果类型: Article
• 署名作者: Kreisz, Philipp; Hellens, Alicia M.; Froeschel, Christian; Krischke, Markus; Maag, Daniel; Feil, Regina; Wildenhain, Theresa; Draken, Jan; Braune, Gabriel; Erdelitsch, Leon; Cecchino, Laura; Wagner, Tobias C.; Ache, Peter; Mueller, Martin J.; Becker, Dirk; Lunn, John E.; Hanson, Johannes; Beveridge, Christine A.; Fichtner, Franziska; Barbier, Francois F.; Weiste, Christoph
• 署名单位: University of Wurzburg; University of Queensland; University of Queensland; Max Planck Society; University of Wurzburg; Umea University; Heinrich Heine University Dusseldorf; Centre National de la Recherche Scientifique (CNRS); Universite de Montpellier; INRAE
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-10724
• DOI: 10.1073/pnas.2313343121
• 发表日期: 2024-02-13
• 关键词: bud outgrowth; factor bzip11; sucrose; expression; transporters; assimilation; protoplasts; dominance; auxin; step

摘要

Plants tightly control growth of their lateral organs, which led to the concept of apical dominance. However, outgrowth of the dormant lateral primordia is sensitive to the plant's nutritional status, resulting in an immense plasticity in plant architecture. While the impact of hormonal regulation on apical dominance is well characterized, the prime importance of sugar signaling to unleash lateral organ formation has just recently emerged. Here, we aimed to identify transcriptional regulators, which control the trade - off between growth of apical versus lateral organs. Making use of locally inducible gain - of- function as well as single and higher - order loss - of- function approaches of the sugar- responsive S1- basic- leucine- zipper (S1-bZIP) transcription factors, we disclosed their largely redundant function in establishing apical growth dominance. Consistently, comprehensive phenotypical and analytical studies of S1-bZIP mutants show a clear shift of sugar and organic nitrogen (N) allocation from apical to lateral organs, coinciding with strong lateral organ outgrowth. Tissue- specific transcriptomics reveal specific clade III SWEET sugar transporters, crucial for long- distance sugar transport to apical sinks and the glutaminase GLUTAMINE AMIDO- TRANSFERASE 1_2.1, involved in N homeostasis, as direct S1-bZIP targets, linking the architectural and metabolic mutant phenotypes to downstream gene regulation. Based on these results, we propose that S1-bZIPs control carbohydrate (C) partitioning from source leaves to apical organs and tune systemic N supply to restrict lateral organ formation by C/N depletion. Knowledge of the underlying mechanisms controlling plant C/N partitioning is of pivotal importance for breeding strategies to generate plants with desired architectural and nutritional characteristics.