Recombinant Human FCRLB/FCRY Protein, CF

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

Recombinant Human FCRLB/FCRY Protein, CF Summary

• Details of Functionality: Measured by its ability to bind human IgG with an estimated K_D < 120 nM.
• Source: Mouse myeloma cell line, NS0-derived human FCRLB/FCRY protein
  Ala18-Ser426 with a C-terminal 6x His tag
• Accession #: Q6BAA4
• N-terminal Sequence:

  Ala18

• Protein/Peptide Type: Recombinant Proteins
• Gene: FCRLB
• Purity: >90%, 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:

  46 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: 65-70 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: >90%, by SDS-PAGE under reducing conditions and visualized by silver stain.
• Reconstitution Instructions: Reconstitute at 100 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 FCRLB/FCRY Protein, CF

• Fc receptor homolog expressed in B cells protein 2
• Fc receptor like 2
• Fc receptor-like and mucin-like 2
• Fc receptor-like and mucin-like protein 2
• Fc receptor-like B
• Fc receptor-like protein 2
• Fc receptor-related protein Y
• FcRL2
• FCRL2FCRLM2
• FCRLB
• FCRLM2
• FCRLY
• FCRY
• FLJ31052
• FREB2
• FREB-2
• FREB-2FcRY
• RP11-474I16.6

Background

FCRLB, also known as FCRL2, FCRY, and FREB2, is a 60 kDa protein with sequence homology to classical Fc receptors. There are at least six type 1 transmembrane FCRL proteins and two that lack transmembrane segments. Each family member contains between three and nine immunoglobulin-like domains. FCRL proteins are differentially expressed within the B cell lineage and can either promote or inhibit B cell proliferation and activation (1, 2). According to R&D Systems testing, FCRLB binds to purified human IgG with high affinity. Human FCRLB shares 82% and 85% amino acid sequence identity with mouse and rat FCRLB, respectively. It contains a putative signal peptide, three immunoglobulin-like domains, and a mucin-like stalk that is rich in Pro, Ser, and Thr residues (1-3). The stalk region also contains di-Leu motifs and an unpaired cysteine (1-3). Alternative splicing generates isoforms with deletions in the putative signal peptide and substitutions and/or truncations in the third Ig-like domain (3). When expressed in transfectants, FCRLB is not secreted but shows a diffuse intracellular localization (3, 4). FCRLB is expressed at a low level in placenta and in B lineage cells of the germinal center (3, 4). It is up-regulated in B cells by BAFF and LPS (5). Among non-hematopoietic cells, FCRLB is expressed in fibroblasts, melanocytes, and melanoma (3, 5). It is preferentially expressed in nonproliferating cells and at the onset of apoptosis (4, 5).

1. Davis, R.S. (2007) Annu. Rev. Immunol. 25:525.
2. Maltais, L.J. et al. (2006) Nat. Immunol. 7:431.
3. Chikaev, N.A. et al. (2005) Genomics 85:264.
4. Wilson, T.J. and M. Colonna (2005) Genes Immun. 6:341.
5. Masuda, K. et al. (2005) Gene 363:32.

Bioinformatics

• Gene Symbol: FCRLB
• Uniprot:
  • Q6BAA4(Human)