Recombinant Human LRRC4 Protein, CF

• Reactivity: Hu
• Applications: Bioactivity
• Format: Carrier-Free

Recombinant Human LRRC4 Protein, CF Summary

• Details of Functionality: Measured by its binding ability in a functional ELISA. When rmNetrin-G2a/Fc Chimera (Catalog # 2744-NG) is coated at 5 μg/mL, rhLRRC4 binds with an apparent K_D < 10 nM.
• Source: Chinese Hamster Ovary cell line, CHO-derived human LRRC4 protein
  Ala39-Lys527, with a C-terminal 6-His tag
• Accession #: Q9HBW1
• N-terminal Sequence: Ala39
• Protein/Peptide Type: Recombinant Proteins
• Gene: LRRC4
• 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:
  • Bioactivity
• Theoretical MW: 55.6 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: 90-110 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: >95%, by SDS-PAGE under reducing conditions and visualized by silver stain
• Reconstitution Instructions: Reconstitute at 400 μg/mL in PBS.

Notes

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

Alternate Names for Recombinant Human LRRC4 Protein, CF

• BAG
• Brain Tumor Associated Protein LRRC4
• Brain Tumor-Associated Protein BAG
• Leucine Rich Repeat Containing 4
• Leucine-Rich Repeat-Containing 4
• Leucine-Rich Repeat-Containing Protein 4
• LRRC4
• NAG14
• Nasopharyngeal Carcinoma-Associated Gene 14 Protein
• Netrin-G2 Ligand
• NGL-2

Background

LRRC4 (Leucine rich repeat/LRR-containing protein 4), also called NGL-2 (netrin-G ligand-2) or NAG14 (nasopharyngeal carcinoma-associated gene 14) is a 55 kDa (predicted) type I transmembrane protein that is a member of the NGL family of synaptic LRR adhesion molecules (1, 2). Human LRRC4 cDNA encodes 653 amino acids (aa) that include a 38 aa signal sequence, a 489 aa extracellular domain (ECD), a 21 aa transmembrane domain, and a 105 aa cytoplasmic domain. The ECD contains nine LRRs (aa 74 ‑ 288), a C2 type Ig like domain (aa 354 ‑ 440), and a Thr-rich segment (aa 455 ‑ 526). Within the ECD, human LRRC4 shares 98% aa identity with mouse and rat, 99% aa identity with canine and bovine, and 99.6% aa identity with equine LRRC4. It also shares 54 ‑ 55% aa identity with family members LRRC4C/NGL-1 and LRRC4B/NGL-3, but each recognizes different ligands (1). LRRC4 is predominantly expressed in the brain on neurons and astrocytes as a ligand for netrin-G2 on the dendritic surface of synaptic neurons (2 - 4). It is proposed to regulate the formation of excitatory synapses via recruitment of PSD-95 to the cytoplasmic domain after aggregation of LRRC4 at the surface (3, 5). It suppresses proliferation by downregulating cell signaling pathways, resulting in altered expression of cell cycle regulating proteins and delay at the late G1 phase (1, 2, 6 - 8). It is thus considered a tumor suppressor protein and is often downregulated in brain tumors, particularly gliomas (1, 2, 6). Forced expression of LRRC4 in tumor cells slows proliferation and promotes differentiation (1, 4, 9). Addition of soluable LRRC4 to cultured neurons reduces excitatory synapse formation (3).

1. Woo, J. et al. (2009) Mol. Cell. Neurosci. 42:1.
2. Zhang, Q. et al. (2005) FEBS Lett. 579:3674.
3. Kim, S. et al. (2006) Nat. Neurosci. 9:1294.
4. Wu, M. et al. (2007) Acta Biochim Biophys Sin (Shanghai) 39:731.
5. Nishimura-Akiyoshi, S. et al. (2007) Proc. Natl. Acad. Sci. USA 104:14801.
6. Wu, M. et al. (2006) Mol. Biol. Cell 17:3534.
7. Wu, M. et al. (2008) J. Cell. Biochem. 103:245.
8. Wu, M. et al. (2008) J. Cell. Physiol. 214:65.
9. Zhang, W. et al. (2008) Genes Brain Behav. 7:385.

Bioinformatics

• Gene Symbol: LRRC4
• Uniprot:
  • Q9HBW1()