Recombinant Rat Dkk-1 Protein

Recombinant Mouse Wnt-3a (Catalog # 1324-WN) induces a dose responsive increase in Wnt reporter activity in HEK293 cells (green circles). Recombinant Rat Dkk-1 (Catalog # 4010‑DK) inhibits a constant dose of 100 ng/mL of Recombinant Mouse Wnt-3a. The ED50 for this effect is 50-300 ng/mL (orange circles).

• Reactivity: Rt
• Applications: Bioactivity

Recombinant Rat Dkk-1 Protein Summary

• Details of Functionality: Measured by its ability to inhibit Wnt induced TCF reporter activity in HEK293 human embryonic kidney cells. Recombinant Rat Dkk-1 inhibits a constant dose of 100 ng/mL of Recombinant Mouse Wnt‑3a (Catalog # 1324-WN). The ED₅₀ for this effect is 50-300 ng/mL.
• Source: Mouse myeloma cell line, NS0-derived rat Dkk-1 protein
  Ser23-His270, with a C-terminal 6-His tag
• Accession #: NP_001099820
• N-terminal Sequence: Ser23
• Protein/Peptide Type: Recombinant Proteins
• Purity: >95%, by SDS-PAGE under reducing conditions and visualized by silver stain.
• Endotoxin Note: <0.01 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity2
• Theoretical MW: 27.6 kDa.
  Disclaimer note: The observed molecular weight of the protein may vary from the listed predicted molecular weight due to post translational modifications, post translation cleavages, relative charges, and other experimental factors.
• SDS-PAGE: 38-42 kDa, reducing conditions

Packaging, Storage & Formulations

• Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  • 12 months from date of receipt, -20 to -70 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
  • 3 months, -20 to -70 °C under sterile conditions after reconstitution.
• Buffer: Lyophilized from a 0.2 μm filtered solution in PBS with BSA as a carrier protein.
• Purity: >95%, by SDS-PAGE under reducing conditions and visualized by silver stain.
• Reconstitution Instructions: Reconstitute at 100 μg/mL in sterile PBS containing at least 0.1% human or bovine serum albumin.

Notes

This product is produced by and ships from R&D Systems, Inc., a Bio-Techne brand.

Alternate Names for Recombinant Rat Dkk-1 Protein

• dickkopf (Xenopus laevis) homolog 1
• dickkopf homolog 1 (Xenopus laevis)
• dickkopf related protein-1
• Dickkopf-1
• dickkopf-related protein 1
• Dkk1
• Dkk-1
• hDkk-1
• SKdickkopf-1 like

Background

Dickkopf related protein 1 (Dkk-1) is the founding member of the Dickkopf family of proteins that includes Dkk-1, -2, -3, -4, and a related protein, Soggy (1, 2). Dkk proteins are secreted proteins that contain two conserved cysteine-rich domains separated by a linker region. Each domain contains ten cysteine residues (1-3). Mature rat Dkk-1 is a 40 kDa glycosylated protein that shows 96%, 86% and 82% aa sequence identity with mouse, human and cow Dkk-1, respectively. It also shows 41% and 34% aa identity with rat Dkk-2 and Dkk-4, respectively. Dkk-1 and Dkk-4 are well documented antagonists of the canonical Wnt signaling pathway (1, 2). This pathway is activated by Wnt engagement of a receptor complex composed of the Frizzled proteins and one of two low-density lipoprotein receptor-related proteins, LRP5 or LRP6 (4). Dkk-1 antagonizes Wnt by forming ternary complexes of LRP5/6 with Kremen1 or Kremen2 (4, 5). Dkk-1/LRP6/Krm2 complex internalization has been shown to downregulate Wnt signaling (4, 5). Dkk-1 is expressed throughout development and antagonizes Wnt-7a during limb development (6, 7). Other sites of expression include developing neurons, hair follicles and the retina of the eye (8, 9). The balance between Wnt signaling and Dkk-1 inhibition is critical for bone formation and homeostasis. Insufficient or excess Dkk-1 activity in bone results in increased or decreased bone density, respectively (8, 10). In adults, Dkk-1 is expressed in osteoblasts and osteocytes, and neurons. Neuronal expression appears to be required for ischemic neuronal death (11).

1. Krupnik, V.E. et al. (1999) Gene 238:301.  
2. Niehrs, C. (2006) Oncogene 25:7469. 
3. Bullock, C.M. et al. (2004) Mol. Pharmacol. 65:582. 
4. Mao, B. et al. (2001) Nature 411:321. 
5. Mao, B. et al. (2002) Nature 417:664.  
6. Kemp, C. et al. (2005) Dev. Dyn. 233:1064.
7. Adamska, M. et al. (2004) Dev. Biol. 272:134.
8. Li, J. et al. (2006) Bone 36:754.
9. Verani, R. et al. (2006) J. Neurochem. 101:242.
10. Morvan, F. et al. (2006) J. Bone Miner. Res. 21:934.
11. Cappuccio, I. et al. (2005) J. Neurosci. 25:2647.

Publications for Dkk-1 (4010-DK)(6)

Publications using 4010-DK

• S Zhang, Y Yang, S Jia, H Chen, Y Duan, X Li, S Wang, T Wang, Y Lyu, G Chen, W Tian Exosome-like vesicles derived from Hertwig&#039;s epithelial root sheath cells promote the regeneration of dentin-pulp tissue Theranostics, 2020-04-27;10(13):5914-5931. 2020-04-27 [PMID: 32483427] (Bioassay, Rat)
• JM Huang, Y Bao, W Xiang, XZ Jing, JC Guo, XD Yao, R Wang, FJ Guo Icariin Regulates the Bidirectional Differentiation of Bone Marrow Mesenchymal Stem Cells through Canonical Wnt Signaling Pathway Evid Based Complement Alternat Med, 2017-12-27;2017(0):8085325. 2017-12-27 [PMID: 29445413] (Bioassay, Rat)
• J Bao, C Ma, J Ran, Y Xiong, S Yan, L Wu Wnt/?-catenin and Hedgehog pathways are involved in the inflammatory effect of Interleukin 18 on rat chondrocytes Oncotarget, 2017-08-24;8(66):109962-109972. 2017-08-24 [PMID: 29299122] (Bioassay, Rat)
• X Kong, X Li, C Zhang, L Zhu, C Liu, Q Qin, C Liu, Q Wang, J Zhu, X Wu, H Wan, W Chen, N Lin Ethyl acetate fraction of Huogu formula inhibits adipogenic differentiation of bone marrow stromal cells via the BMP and Wnt signaling pathways Int. J. Biol. Sci., 2017-04-07;13(4):480-491. 2017-04-07 [PMID: 28529456] (Bioassay, Rat)
• Ting Cai WNT/?-catenin signaling promotes VSMCs to osteogenic transdifferentiation and calcification through directly modulating Runx2 gene expression Exp Cell Res, 2016-06-16;0(0):. 2016-06-16 [PMID: 27321958] (Bioassay, Rat)
• Smith A, Lewis F, Aquila I, Waring C, Nocera A, Agosti V, Nadal-Ginard B, Torella D, Ellison G Isolation and characterization of resident endogenous c-Kit+ cardiac stem cells from the adult mouse and rat heart. Nat Protoc, 2014-06-19;9(7):1662-81. 2014-06-19 [PMID: 24945383] (Bioassay, Rat)

Bioinformatics

• Uniprot:
  • NP_001099820()