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Structural analysis of a function-associated loop mutant of the substrate-recognition domain of Fbs1 ubiquitin ligase.

ABSTRACT: The SCF ubiquitin ligase comprises four components: Skp1, Cul1, Rbx1 and a variable-subunit F-box protein. The F-box protein Fbs1, which recognizes the N-linked glycoproteins, is involved in the endoplasmic reticulum-associated degradation pathway. Although FBG3, another F-box protein, shares 51% sequence identity with Fbs1, FBG3 does not bind glycoproteins. To investigate the sequence-structure relationship of the substrate-binding pocket, the crystal structure of a mutant substrate-binding domain of Fbs1 in which the six nonconserved regions (β1, β2-β3, β3-β4, β5-β6, β7-β8 and β9-β10) of Fbs1 were substituted with those of FBG3 was determined. The substrate-binding pocket of this model exhibits structural features that differ from those of Fsb1.

SUBMITTER: Nishio K

PROVIDER: S-EPMC4973303 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Structural analysis of a function-associated loop mutant of the substrate-recognition domain of Fbs1 ubiquitin ligase.

Nishio Kazuya K Yoshida Yukiko Y Tanaka Keiji K Mizushima Tsunehiro T

Acta crystallographica. Section F, Structural biology communications 20160727 Pt 8

The SCF ubiquitin ligase comprises four components: Skp1, Cul1, Rbx1 and a variable-subunit F-box protein. The F-box protein Fbs1, which recognizes the N-linked glycoproteins, is involved in the endoplasmic reticulum-associated degradation pathway. Although FBG3, another F-box protein, shares 51% sequence identity with Fbs1, FBG3 does not bind glycoproteins. To investigate the sequence-structure relationship of the substrate-binding pocket, the crystal structure of a mutant substrate-binding dom ...[more]

PMID: 27487926

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