InterPro domain: IPR036296

SKP1 (together with SKP2) was identified as an essential component of the cyclin A-CDK2 S phase kinase complex [ 1 ]. It was found to bind several F-box containing proteins (e.g., Cdc4, Skp2, cyclin F) and to be involved in the ubiquitin protein degradation pathway. A yeast homologue of SKP1 (P52286) was identified in the centromere bound kinetochore complex [ 2 ] and is also involved in the ubiquitin pathway [ 3 ]. In Dictyostelium discoideum (Slime mold) FP21 was shown to be glycosylated in the cytosol and has homology to SKP1 [ 4 ].

This entry represents the superfamily of a dimerisation domain found at the C-terminal of SKP1 proteins [ 5 ], as well as in subunit D of the centromere DNA-binding protein complex Cbf3 [ 6 ]. This domain is multi-helical in structure, and consists of an interlocked herterodimer in F-box proteins.

1. Structure of the VHL-ElonginC-ElonginB complex: implications for VHL tumor suppressor function. Science 284, 455-61
2. The Saccharomyces cerevisiae kinetochore contains a cyclin-CDK complexing homologue, as identified by in vitro reconstitution. EMBO J. 15, 3611-20
3. Regulating the yeast kinetochore by ubiquitin-dependent degradation and Skp1p-mediated phosphorylation. Cell 91, 491-500
4. Characterization of FP21, a cytosolic glycoprotein from Dictyostelium. J. Biol. Chem. 270, 3022-30
5. Insights into SCF ubiquitin ligases from the structure of the Skp1-Skp2 complex. Nature 408, 381-6
6. Structural basis for phosphodependent substrate selection and orientation by the SCFCdc4 ubiquitin ligase. Cell 112, 243-56