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Crystal structure of the UBR-box from UBR6/FBXO11 reveals domain swapping mediated by zinc binding.

ABSTRACT: The UBR-box is a 70-residue zinc finger domain present in the UBR family of E3 ubiquitin ligases that directly binds N-terminal degradation signals in substrate proteins. UBR6, also called FBXO11, is an UBR-box containing E3 ubiquitin ligase that does not bind N-terminal signals. Here, we present the crystal structure of the UBR-box domain from human UBR6. The dimeric crystal structure reveals a unique form of domain swapping mediated by zinc coordination, where three independent protein chains come together to regenerate the topology of the monomeric UBR-box fold. Analysis of the structure suggests that the absence of N-terminal residue binding arises from the lack of an amino acid binding pocket.

SUBMITTER: Munoz-Escobar J

PROVIDER: S-EPMC5606531 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Crystal structure of the UBR-box from UBR6/FBXO11 reveals domain swapping mediated by zinc binding.

Muñoz-Escobar Juliana J Kozlov Guennadi G Gehring Kalle K

Protein science : a publication of the Protein Society 20170725 10

The UBR-box is a 70-residue zinc finger domain present in the UBR family of E3 ubiquitin ligases that directly binds N-terminal degradation signals in substrate proteins. UBR6, also called FBXO11, is an UBR-box containing E3 ubiquitin ligase that does not bind N-terminal signals. Here, we present the crystal structure of the UBR-box domain from human UBR6. The dimeric crystal structure reveals a unique form of domain swapping mediated by zinc coordination, where three independent protein chains ...[more]

PMID: 28691247

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