title: The Arabidopsis O-fucosyltransferase SPINDLY activates nuclear growth repressor DELLA.
abstract: Plant development requires coordination among complex signaling networks to enhance the plant's adaptation to changing environments. DELLAs, transcription regulators originally identified as repressors of phytohormone gibberellin signaling, play a central role in integrating multiple signaling activities via direct protein interactions with key transcription factors. Here, we found that DELLA is mono-O-fucosylated by the novel O-fucosyltransferase SPINDLY (SPY) in Arabidopsis thaliana. O-fucosylation activates DELLA by promoting its interaction with key regulators in brassinosteroid- and light-signaling pathways, including BRASSINAZOLE-RESISTANT1 (BZR1), PHYTOCHROME-INTERACTING-FACTOR3 (PIF3) and PIF4. Moreover, spy mutants displayed elevated responses to gibberellin and brassinosteroid, and increased expression of common target genes of DELLAs, BZR1 and PIFs. Our study revealed that SPY-dependent protein O-fucosylation plays a key role in regulating plant development. This finding may have broader importance because SPY orthologs are conserved in prokaryotes and eukaryotes, thus suggesting that intracellular O-fucosylation may regulate a wide range of biological processes in diverse organisms.
authors.affiliation: Department of Biology, Duke University, Durham, North Carolina, USA.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Zentella
authors.affiliation: Department of Biology, Duke University, Durham, North Carolina, USA.
authors.forename: Ning
authors.initials: N
authors.lastname: Sui
authors.affiliation: Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Barnhill
authors.affiliation: Department of Biology, Duke University, Durham, North Carolina, USA.
authors.forename: Wen-Ping
authors.initials: WP
authors.lastname: Hsieh
authors.affiliation: Department of Biology, Duke University, Durham, North Carolina, USA.
authors.forename: Jianhong
authors.initials: J
authors.lastname: Hu
authors.affiliation: Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Shabanowitz
authors.affiliation: Department of Biochemistry, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Boyce
authors.affiliation: Department of Plant Biology, University of Minnesota, Saint Paul, Minnesota, USA.
authors.forename: Neil E
authors.identifier: 0000-0001-5393-7743
authors.initials: NE
authors.lastname: Olszewski
authors.affiliation: Department of Biochemistry, Duke University Medical Center, Durham, North Carolina, USA.|Department of Chemistry, Duke University, Durham, North Carolina, USA.
authors.forename: Pei
authors.initials: P
authors.lastname: Zhou
authors.affiliation: Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA.|Department of Pathology, University of Virginia, Charlottesville, Virginia, USA.
authors.forename: Donald F
authors.initials: DF
authors.lastname: Hunt
authors.affiliation: Department of Biology, Duke University, Durham, North Carolina, USA.
authors.forename: Tai-Ping
authors.initials: TP
authors.lastname: Sun
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D005647:Fucosyltransferases / Q000235:genetics / Q000378:metabolism*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C109555:GAI protein, Arabidopsis; D012097:Repressor Proteins; C101465:SPY protein, Arabidopsis; D005647:Fucosyltransferases