GID2, an F-box subunit of the SCF E3 complex, specifically interacts with phosphorylated SLR1 protein and regulates the gibberellin-dependent degradation of SLR1 in rice.
The phytohormone gibberellin (GA) controls growth and development in plants. Previously, we identified a rice F-box protein, gibberellin-insensitive dwarf2 (GID2), which is essential for GA-mediated DELLA protein degradation. In this study, we analyzed the biological and molecular biological properties of GID2. Expression of GID2 preferentially occurred in rice organs actively synthesizing GA. Domain analysis of GID2 revealed that the C-terminal regions were essential for the GID2 function, but not the N-terminal region. Yeast two-hybrid assay and immunoprecipitation experiments demonstrated that GID2 is a component of the SCF complex through an interaction with a rice ASK1 homolog, OsSkp15. Furthermore, an in vitro pull-down assay revealed that GID2 specifically interacted with the phosphorylated Slender Rice 1 (SLR1). Taken these results together, we conclude that the phosphorylated SLR1 is caught by the SCFGID2 complex through an interacting affinity between GID2 and phosphorylated SLR1, triggering the ubiquitin-mediated degradation of SLR1.
Gomi
Kenji
K
Bioscience and Biotechnology Center, Nagoya University, Chikusa, Nagoya 464-8601, Japan.
Sasaki
Akie
A
Itoh
Hironori
H
Ueguchi-Tanaka
Miyako
M
Ashikari
Motoyuki
M
Kitano
Hidemi
H
Matsuoka
Makoto
M
D044842:Cullin Proteins / Q000235:genetics / Q000378:metabolism; D044783:F-Box Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D005875:Gibberellins / Q000494:pharmacology*; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D010766:Phosphorylation; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000494:pharmacology; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D044786:S-Phase Kinase-Associated Proteins / Q000235:genetics / Q000378:metabolism; D044843:SKP Cullin F-Box Protein Ligases / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D043743:Ubiquitin-Protein Ligase Complexes / Q000235:genetics* / Q000378:metabolism
D044842:Cullin Proteins; D044783:F-Box Proteins; D005875:Gibberellins; D008164:Luminescent Proteins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D044786:S-Phase Kinase-Associated Proteins; D049452:Green Fluorescent Proteins; D043743:Ubiquitin-Protein Ligase Complexes; D044843:SKP Cullin F-Box Protein Ligases