Understanding gibberellic acid signaling--are we there yet?
The phytohormone gibberellic acid (GA) controls important aspects of plant growth such as seed germination, elongation growth, and flowering. The key components of the GA signaling pathway have been identified over the past 10 years. The current view is that GA binds to a soluble GID1 receptor, which interacts with the DELLA repressor proteins in a GA-dependent manner and thereby induces DELLA protein degradation via the E3 ubiquitin ligase SCF(GID2/SLY1). GA-dependent growth responses can generally be correlated with and be explained by changes in DELLA repressor abundance, where the DELLA repressor exerts a growth restraint that is relieved upon its degradation. However, it is obvious that other mechanisms must exist that control the activity of this pathway. This review discusses recent advances in the understanding of GA signaling, of its homeostasis, and of its cross-talk with other signaling pathways.
Schwechheimer
Claus
C
Department of Developmental Genetics, Center for Plant Molecular Biology, Tübingen University, Auf der Morgenstelle 5, 72076 Tübingen, Germany. claus.schwechheimer@zmbp.uni-tuebingen.de
D029681:Arabidopsis Proteins / Q000378:metabolism; D005875:Gibberellins / Q000378:metabolism*; D006706:Homeostasis / Q000502:physiology*; D010940:Plant Proteins / Q000378:metabolism; D010944:Plants / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D020239:Receptor Cross-Talk / Q000502:physiology*; D011956:Receptors, Cell Surface / Q000378:metabolism; D044843:SKP Cullin F-Box Protein Ligases / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*
D029681:Arabidopsis Proteins; C512225:GID1a protein, Arabidopsis; D005875:Gibberellins; D010940:Plant Proteins; D011956:Receptors, Cell Surface; C007842:gibberellic acid; D044843:SKP Cullin F-Box Protein Ligases