The Arabidopsis SLEEPY1 gene encodes a putative F-box subunit of an SCF E3 ubiquitin ligase.
The Arabidopsis SLY1 (SLEEPY1) gene positively regulates gibberellin (GA) signaling. Positional cloning of SLY1 revealed that it encodes a putative F-box protein. This result suggests that SLY1 is the F-box subunit of an SCF E3 ubiquitin ligase that regulates GA responses. The DELLA domain protein RGA (repressor of ga1-3) is a repressor of GA response that appears to undergo GA-stimulated protein degradation. RGA is a potential substrate of SLY1, because sly1 mutations cause a significant increase in RGA protein accumulation even after GA treatment. This result suggests SCF(SLY1)-targeted degradation of RGA through the 26S proteasome pathway. Further support for this model is provided by the observation that an rga null allele partially suppresses the sly1-10 mutant phenotype. The predicted SLY1 amino acid sequence is highly conserved among plants, indicating a key role in GA response.
United States Department of Agriculture-Agricultural Research Service, Washington State University, Pullman 99164-6420, USA.
Karen M
KM
McGinnis
Stephen G
SG
Thomas
Jonathan D
JD
Soule
Lucia C
LC
Strader
Janice M
JM
Zale
Tai-ping
TP
Sun
Camille M
CM
Steber
D019883:Alkyl and Aryl Transferases; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D005875:Gibberellins / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D010453:Peptide Synthases / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins; D021122:Protein Subunits / Q000235:genetics* / Q000378:metabolism; D044843:SKP Cullin F-Box Protein Ligases; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D029681:Arabidopsis Proteins; D005875:Gibberellins; D010940:Plant Proteins; D021122:Protein Subunits; D014157:Transcription Factors; C007842:gibberellic acid; D006899:Mixed Function Oxygenases; C089210:gibberellin, 2-oxoglutarate-oxygen oxidoreductase (20-hydroxylating, oxidizing); C108186:gibberellin 3beta-hydroxylase; D044843:SKP Cullin F-Box Protein Ligases; D019883:Alkyl and Aryl Transferases; C476121:SLY1 protein, Arabidopsis; D010453:Peptide Synthases