TY - JOUR
T1 - Identification of Elongin C and Skp1 sequences that determine cullin selection
AU - Yan, Qin
AU - Kamura, Takumi
AU - Cai, Yong
AU - Jin, Jingji
AU - Ivan, Mircea
AU - Mushegian, Arcady
AU - Conaway, Ronald C.
AU - Conaway, Joan Weliky
PY - 2004/10/8
Y1 - 2004/10/8
N2 - The multiprotein von Hippel-Lindau (VHL) tumor suppressor and Skp1-Cul1-F-box protein (SCF) complexes belong to families of structurally related E3 ubiquitin ligases. In the VHL ubiquitin ligase, the VHL protein serves as the substrate recognition subunit, which is linked by the adaptor protein Elongin C to a heterodimeric Cul2/Rbx1 module that activates ubiquitylation of target proteins by the E2 ubiquitin-conjugating enzyme Ubc5. In SCF ubiquitin ligases, F-box proteins serve as substrate recognition subunits, which are linked by the Elongin C-like adaptor protein Skp1 to a Cul1/Rbx1 module that activates ubiquitylation of target proteins, in most cases by the E2 Cdc34. In this report, we investigate the functions of the Elongin C and Skp1 proteins in reconstitution of VBDL and SCF ubiquitin ligases. We identify Elongin C and Skp1 structural elements responsible for selective interaction with their cognate Cullin/Hbx1 modules. In addition, using altered specificity Elongin C and F-box protein mutants, we investigate models for the mechanism underlying E2 selection by VHL and SCF ubiquitin ligases. Our findings provide evidence that E2 selection by VHL and SCF ubiquitin ligases is determined not solely by the Cullin/ Rbx1 module, the target protein, or the integrity of the substrate recognition subunit but by yet to be elucidated features of these macromolecular complexes.
AB - The multiprotein von Hippel-Lindau (VHL) tumor suppressor and Skp1-Cul1-F-box protein (SCF) complexes belong to families of structurally related E3 ubiquitin ligases. In the VHL ubiquitin ligase, the VHL protein serves as the substrate recognition subunit, which is linked by the adaptor protein Elongin C to a heterodimeric Cul2/Rbx1 module that activates ubiquitylation of target proteins by the E2 ubiquitin-conjugating enzyme Ubc5. In SCF ubiquitin ligases, F-box proteins serve as substrate recognition subunits, which are linked by the Elongin C-like adaptor protein Skp1 to a Cul1/Rbx1 module that activates ubiquitylation of target proteins, in most cases by the E2 Cdc34. In this report, we investigate the functions of the Elongin C and Skp1 proteins in reconstitution of VBDL and SCF ubiquitin ligases. We identify Elongin C and Skp1 structural elements responsible for selective interaction with their cognate Cullin/Hbx1 modules. In addition, using altered specificity Elongin C and F-box protein mutants, we investigate models for the mechanism underlying E2 selection by VHL and SCF ubiquitin ligases. Our findings provide evidence that E2 selection by VHL and SCF ubiquitin ligases is determined not solely by the Cullin/ Rbx1 module, the target protein, or the integrity of the substrate recognition subunit but by yet to be elucidated features of these macromolecular complexes.
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U2 - 10.1074/jbc.M408018200
DO - 10.1074/jbc.M408018200
M3 - Article
C2 - 15280393
AN - SCOPUS:5644244197
SN - 0021-9258
VL - 279
SP - 43019
EP - 43026
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 41
ER -