F-box domain found in Arabidopsis thaliana transport inhibitor response 1 protein (TIR1), coronatine-insensitive protein 1 (COI1) and similar proteins
TIR1, also called F-box/LRR-repeat protein 1 (FBL1), is part of an SCF (SKP1-cullin-F-box) protein ligase complex that promotes the ubiquitin-dependent proteolysis of a family of transcriptional regulators known as Aux/IAAs in an auxin-dependent manner. TIR1 is an auxin receptor that plays a potential role in plant hormone signaling. COI1, also called F-box/LRR-repeat protein 2 (FBL2), is the substrate-recruiting module of an SCF ubiquitin E3 ligase complex. It mediates jasmonate signalling by promoting hormone-dependent ubiquitylation and degradation of transcriptional repressor JASMONATE ZIM-domain (JAZ) family proteins. This subfamily also includes Arabidopsis thaliana EIN3-binding F-box protein 1 (EBF1). EBF1, also called F-box/LRR-repeat protein 6 (FBL6), is a component of the SCF(EBF1) E3 ubiquitin ligase complex, which may mediate the ubiquitination and subsequent proteasomal degradation of target proteins (probably including EIN3 and EIL1). The F-box domain has a role in mediating protein-protein interactions in a variety of contexts, such as polyubiquitination, transcription elongation, centromere binding and translational repression.
Feature 1:Skp1 binding site [polypeptide binding site]
Evidence:
Structure:2P1M; Arabidopsis thaliana TIR1 in complex with Skp1, contacts at 4A
Comment:F-box proteins participate in SCF (Skp1-Cul1-F-box protein) complexes that function as ubiquitin E3 ligases, where the role of the F-box protein is to recruit target substrates.
Jiyao W et al.(2023). "The conserved domain database in 2023.",