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Structural and functional characterization of Rpn12 identifies residues required for Rpn10 proteasome incorporation.

ABSTRACT: The ubiquitin-proteasome system targets selected proteins for degradation by the 26S proteasome. Rpn12 is an essential component of the 19S regulatory particle and plays a role in recruiting the extrinsic ubiquitin receptor Rpn10. In the present paper we report the crystal structure of Rpn12, a proteasomal PCI-domain-containing protein. The structure helps to define a core structural motif for the PCI domain and identifies potential sites through which Rpn12 might form protein-protein interactions. We demonstrate that mutating residues at one of these sites impairs Rpn12 binding to Rpn10 in vitro and reduces Rpn10 incorporation into proteasomes in vivo.

SUBMITTER: Boehringer J

PROVIDER: S-EPMC3481250 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Structural and functional characterization of Rpn12 identifies residues required for Rpn10 proteasome incorporation.

Boehringer Jonas J Riedinger Christiane C Paraskevopoulos Konstantinos K Johnson Eachan O D EO Lowe Edward D ED Khoudian Christina C Smith Dominique D Noble Martin E M ME Gordon Colin C Endicott Jane A JA

The Biochemical journal 20121101 1

The ubiquitin-proteasome system targets selected proteins for degradation by the 26S proteasome. Rpn12 is an essential component of the 19S regulatory particle and plays a role in recruiting the extrinsic ubiquitin receptor Rpn10. In the present paper we report the crystal structure of Rpn12, a proteasomal PCI-domain-containing protein. The structure helps to define a core structural motif for the PCI domain and identifies potential sites through which Rpn12 might form protein-protein interactio ...[more]

PMID: 22906049

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