Skp1 Dimerization Conceals Its F-Box Protein Binding Site.

ABSTRACT: Skp1 is an adapter that links F-box proteins to cullin-1 in the Skp1/cullin-1/F-box (SCF) protein family of E3 ubiquitin ligases that targets specific proteins for polyubiquitination and subsequent protein degradation. Skp1 from the amoebozoan Dictyostelium forms a stable homodimer in vitro with a K_d of 2.5 μM as determined by sedimentation velocity studies yet is monomeric in crystal complexes with F-box proteins. To investigate the molecular basis for the difference, we determined the solution NMR structure of a doubly truncated Skp1 homodimer (Skp1ΔΔ). The solution structure of the Skp1ΔΔ dimer reveals a 2-fold symmetry with an interface that buries ∼750 Ų of predominantly hydrophobic surface. The dimer interface overlaps with subsite 1 of the

SUBMITTER: Kim HW 

PROVIDER: S-EPMC7521599 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature