GIBBERELLIN INSENSITIVE DWARF1 Encodes a Soluble Receptor for Gibberellin

Nature. 2005 Sep 29;437(7059):693-8. doi: 10.1038/nature04028.

Abstract

Gibberellins (GAs) are phytohormones that are essential for many developmental processes in plants. It has been postulated that plants have both membrane-bound and soluble GA receptors; however, no GA receptors have yet been identified. Here we report the isolation and characterization of a new GA-insensitive dwarf mutant of rice, gid1. The GID1 gene encodes an unknown protein with similarity to the hormone-sensitive lipases, and we observed preferential localization of a GID1-green fluorescent protein (GFP) signal in nuclei. Recombinant glutathione S-transferase (GST)-GID1 had a high affinity only for biologically active GAs, whereas mutated GST-GID1 corresponding to three gid1 alleles had no GA-binding affinity. The dissociation constant for GA4 was estimated to be around 10(-7) M, enough to account for the GA dependency of shoot elongation. Moreover, GID1 bound to SLR1, a rice DELLA protein, in a GA-dependent manner in yeast cells. GID1 overexpression resulted in a GA-hypersensitive phenotype. Together, our results indicate that GID1 is a soluble receptor mediating GA signalling in rice.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Binding, Competitive
  • Cloning, Molecular
  • Epistasis, Genetic
  • Genes, Plant / genetics
  • Gibberellins / metabolism*
  • Gibberellins / pharmacology
  • Molecular Sequence Data
  • Mutation / genetics
  • Oryza / drug effects
  • Oryza / genetics*
  • Oryza / metabolism*
  • Phenotype
  • Plant Proteins / chemistry
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Protein Binding*
  • Solubility
  • Sterol Esterase / chemistry

Substances

  • Gibberellins
  • Plant Proteins
  • Sterol Esterase

Associated data

  • GENBANK/AB211399