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-Structure paper
タイトル | The structure of the 26S proteasome subunit Rpn2 reveals its PC repeat domain as a closed toroid of two concentric α-helical rings. |
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ジャーナル・号・ページ | Structure, Vol. 20, Issue 3, Page 513-521, Year 2012 |
掲載日 | 2012年3月7日 |
著者 | Jun He / Kiran Kulkarni / Paula C A da Fonseca / Dasha Krutauz / Michael H Glickman / David Barford / Edward P Morris / |
PubMed 要旨 | The 26S proteasome proteolyses ubiquitylated proteins and is assembled from a 20S proteolytic core and two 19S regulatory particles (19S-RP). The 19S-RP scaffolding subunits Rpn1 and Rpn2 function to ...The 26S proteasome proteolyses ubiquitylated proteins and is assembled from a 20S proteolytic core and two 19S regulatory particles (19S-RP). The 19S-RP scaffolding subunits Rpn1 and Rpn2 function to engage ubiquitin receptors. Rpn1 and Rpn2 are characterized by eleven tandem copies of a 35-40 amino acid repeat motif termed the proteasome/cyclosome (PC) repeat. Here, we reveal that the eleven PC repeats of Rpn2 form a closed toroidal structure incorporating two concentric rings of α helices encircling two axial α helices. A rod-like N-terminal domain consisting of 17 stacked α helices and a globular C-terminal domain emerge from one face of the toroid. Rpn13, an ubiquitin receptor, binds to the C-terminal 20 residues of Rpn2. Rpn1 adopts a similar conformation to Rpn2 but differs in the orientation of its rod-like N-terminal domain. These findings have implications for understanding how 19S-RPs recognize, unfold, and deliver ubiquitylated substrates to the 20S core. |
リンク | Structure / PubMed:22405010 |
手法 | EM (単粒子) / X線回折 |
解像度 | 2.7 - 25.0 Å |
構造データ | EMDB-2026: PDB-4ady: |
化合物 | ChemComp-HOH: |
由来 |
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キーワード | PROTEIN BINDING / RPN1 / PC REPEAT |