Enabling Protein Degradation Drug Discovery

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  • Name
    Catalogue Number
    Size
    Price
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  • Name:
    Cul3/Rbx1 [untagged]
    Catalogue Number:
    63-1003-025
    Size:
    25 µg
    Price:
    £250
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  • Species
    human
  • Source
    Insect (Sf21)
  • Quantity
    25µg
  • Storage
    -70°C
  • Concentration
    0.5 mg/ml
  • Formulation
    50 mM HEPES pH 7.5, 150 mM sodium chloride, 2 mM dithiothreitol, 10% glycerol
  • Molecular Weight
    Cul3= 89kDa; Rbx1=12kDa
  • Stability
    12 months at -70°C; aliquot as required
  • Protein Sequence
    Accession number: Cul3=NP_003581.1; Rbx1=NP_055063.1. For full protein sequence information download the Certificate of Analysis pdf.
  • QA; Protein Identification
    Confirmed by mass spectrometry.
  • QA; Activity
    E3 Ligase Assay: The activity of Cul3/Rbx1 was validated indirectly through its ability to act as a substrate for Neddylation in the presence of the NEDD8 E3 ligase His-DCNL2 and thioester-loaded His-Ube2M-NEDD8. Incubation of Cul3/Rbx1 and thioester loaded His-Ube2M-NEDD8 in the presence or absence of His-DCNL2 at 4°C was compared at two time points T0 and T2 minutes. Neddylation of the Cul3 subunit in the presence of His-DCNL2 was demonstrated. 

The enzymes of the ubiquitylation pathway play a pivotal role in a number of cellular processes including the regulated and targeted proteasome dependent degradation of substrate proteins. Three classes of enzymes are involved in the process of ubiquitylation; activating enzymes (E1s), conjugating enzymes (E2s) and protein ligases (E3s). Cullin-RING-Ligases (CRLs) are one largest class of ubiquitin E3 ligases and the enzymes of the NEDDylation pathway play a pivotal role in the activation of these, akin to ubiquitylation, the E1 activating enzyme (APP-BP1/UBA3 heterodimer) and the E2 conjugating enzymes (UBE2M or UBE2F) are involved in mammalian NEDDylation of the Cullin Ring Ligases (CRLs) (Meyer-Schaller et al., 2009; Huang et al., 2011; Morimoto et al., 2003). The human Cullin1-5 genes were first described by Kipreos et al. (1996). Cullin RING ligases (CRL) comprise the largest subfamily of ubiquitin ligases which are activated by Neddylation. CRLs are involved in cell cycle regulation, DNA replication, DNA damage response (DDR). CRLs contain subunits including, a scaffold protein (cullin family protein), a Ring finger protein either Rbx1 (Cul1-4) or Rbx2 (Cul5) that binds a ubiquitin E2 Ube2M or Ube2F respectively (Sarikas et al., 2011; Skowyra et al., 1997). Cul3 expression in human fibroblasts is induced by phorbol 12-myristate 13-acetate (PMA) and suppressed by salicylate (Du et al., 1998). The Cul3/Kelch like 9(KLHL9) /Kelch like 13 (KLHL13) complex is an E3 ligase that controls the behavior of Aurora B on mitotic chromosomes and thereby coordinating mitotic progression and completion of cytokinesis (Sumara et al., 2007). Interaction of Cul3 with Kelch like 7 (KLHL7) leads to the ubiquitylation of the dopamine receptor D4 (DRD4) (Rondou et al., 2008). 

References:    

Du M, Sansores-Garcia L, Zu Z, Wu K K, (1998) Cloning and expression analysis of a novel salicylate suppressible gene, Hs-CUL-3, a member of cullin/Cdc53 family. J. Biol. Chem. 273, 24289-24292.

Huang G, Kaufman A J, Ramanathan Y, Singh B, (2011) SCCRO (DCUN1D1) promotes nuclear translocation and assembly of the neddylation E3 complex, J Biol Chem 286, 10297-10304.

Kipreos ET, Lander LE, Wing JP, He WW, Hedgecock E.M. (1996) cul-1 is required for cell cycle exit in C. elegans and identifies a novel gene family, Cell 85, 829-839.

Meyer-Schaller N, Chou YC, Sumara I, Martin DD, Kurz T, Katheder N, Hofmann K, Berthiaume LG, Sicheri F, Peter M. (2009) The human Dcn1-like protein DCNL3 promotes Cul3 neddylation at membranes, Proc Natl Acad Sci U S A 106, 12365-12370.

Morimoto M, Nishida T, Nagayama Y, Yasuda H. (2003) Nedd8-modification of Cul1 is promoted by Roc1 as a Nedd8-E3 ligase and regulates its stability, Biochem Biophys Res Commun 301, 392-398.

Rondou P, Haegeman G, Vanhoenacker P, Van Craenenbroeck K, (2008) BTB protein KLHL12 targets the dopamine D4 receptor for ubiquitination by a Cul3-based E3 ligase. J. Biol. Chem. 283 11083-11096.

Sarikas, A., Hartmann, T. and Pan, Z.Q. (2011) The cullin protein family, Genome biology 12, 220.

Skowyra D, Craig KL, Tyers M, Elledge SJ, Harper J.W. (1997) F-box proteins are receptors that recruit phosphorylated substrates to the SCF ubiquitin-ligase complex, Cell 91, 209-219.

Sumara I, Quadroni M, Frei C, Olma M. H, Sumara G, Ricci R, Peter M. A. (2007) Cul3-based E3 ligase removes Aurora B from mitotic chromosomes, regulating mitotic progression and completion of cytokinesis in human cells. Dev. Cell 12, 887-900.