Recombinant Rat Kremen-2 Protein, CF

• Reactivity: Rt
• Applications: Binding Activity
• Format: Carrier-Free

Recombinant Rat Kremen-2 Protein, CF Summary

• Details of Functionality: Measured by its binding ability in a functional ELISA. Immobilized rrKremen-2 at 4 µg/mL can bind rhDkk-1 with an apparent K_D < 15 nM.
• Source: Mouse myeloma cell line, NS0-derived rat Kremen-2 protein
  Gly53-Arg395, with a C-terminal 6-His tag
• Accession #: XP_220206
• N-terminal Sequence: Gly53
• Protein/Peptide Type: Recombinant Proteins
• Purity: >85%, 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:
  • Binding Activity
• Theoretical MW: 37.5 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: 45-55 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.
• Purity: >85%, by SDS-PAGE under reducing conditions and visualized by silver stain
• Reconstitution Instructions: Reconstitute at 100 μg/mL in sterile PBS.

Notes

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

Alternate Names for Recombinant Rat Kremen-2 Protein, CF

• Dickkopf receptor 2
• kremen protein 2
• Kremen2
• Kremen-2
• kringle containing transmembrane protein 2
• Kringle domain-containing transmembrane protein 2
• KRM2Kringle-containing protein marking the eye and the nose
• MGC10791
• MGC16709

Background

Kremen (Kringle-containing protein marking the eye and the nose) proteins are type I transmembrane proteins that contain extracellular kringle, WSC and CUB domains, and an intracellular region with no conserved motifs (1). Two related molecules, Kremen-1 and -2, have been identified. Kremens bind with high affinity to a subset of the secreted Dickkopf proteins (Dkk-1, -2, and -4) to modulate the canonical Wnt signaling pathway (2). This pathway is transduced by a ternary receptor complex composed of Wnt, the seven-transmembrane domain receptor Frizzled, and the LDL-receptor-related protein 5/6 (LRP5/6) coreceptor (3, 4). Dkk-1 and -4 bind directly to the LRP5/6 coreceptor to antagonize the canonical Wnt/ beta -catenin signaling pathway. The planar cell polarity (PCP) signaling pathway is not affected as it does not involve LRP5/6 (2). In contrast, Dkk-3 has no effect on Wnt signaling. Dkk-2 can function either as an LRP agonist or antagonist, depending on whether or not the cell expresses Kremen (5). Kremen cooperates with Dkk to antagonize Wnt signaling via formation of a Kremen-Dkk-LRP ternary complex which is internalized and cleared from the cell surface (4). Binding requires all three extracellular domains of Kremen, and the second cysteine-rich domain of Dkk (4). The predicted rat Kremen-2 cDNA encodes a 490 amino acid (aa) glycosylated protein with a 51 aa signal peptide, a 340 aa extracellular domain, a 24 aa transmembrane domain, and a 75 aa cytoplasmic domain. Within the ECD, rat Kremen-2 shares 91% and 98% aa sequence identity with human and mouse Kremen-2, respectively, and 46% with rat Kremen-1.

1. Nakamura, T. et al. (2001) Biochim. Biophys. Acta 1518:63.
2. Niehrs, C. (2006) Oncogene 25:7469.
3. Davidson G. et al. (2002) Development 129:5587.
4. Mao, B. et al. (2002) Nature 417:664.
5. Mao, B. and C. Niehrs (2003) Gene 302:179.

Bioinformatics

• Uniprot:
  • XP_220206()