Recombinant Human TMEM106B Fc Chimera Protein, CF

Recombinant Human TMEM106B Fc Chimera Protein (Catalog # 11644-TM) binds Recombinant SARS-CoV-2 Spike RBD His-tag (HEK293 Expressed) (10500-CV) with ED50 < 2.00 μg/mL

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

Recombinant Human TMEM106B Fc Chimera Protein, CF Summary

• Details of Functionality: Measured by its binding ability in a functional ELISA. Recombinant Human TMEM106B Fc Chimera (Catalog # 11644-TM) binds Recombinant SARS-CoV-2 Spike RBD His-tag (HEK293 Expressed) (Catalog # 10500-CV) with ED₅₀ <2.00 μg/mL.
• Source: Human embryonic kidney cell, HEK293-derived human TMEM106B protein
  

  MD	Human IgG1 (Pro100-Lys330)	IEGR	Human TREM106B (Pro118-Gln274) Accession # NP_001127704.1
  N-terminus			C-terminus

• N-terminal Sequence: Met
• Structure / Form: Disulfide linked homodimer
• Protein/Peptide Type: Recombinant Proteins
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining
• Endotoxin Note: <0.10 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity
• Theoretical MW: 45 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: >60 kDa, under reducing conditions.

Packaging, Storage & Formulations

• Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  • 6 months from date of receipt, -70 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after opening.
  • 3 months, -20 to -70 °C under sterile conditions after opening.
• Buffer: Supplied as a 0.2 μm filtered solution in PBS with Trehalose.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining

Notes

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

Alternate Names for Recombinant Human TMEM106B Fc Chimera Protein, CF

• TMEM106B
• transmembrane protein 106B

Background

SARS-CoV-2 is associated with broad tissue tropism, a characteristic often determined by the availability of entry receptors on host cells. TMEM106B, a lysosomal transmembrane protein, can serve as an alternative receptor for SARS-CoV-2 entry into angiotensin-converting enzyme 2 (ACE2)-negative cells. Spike substitution E484D increased TMEM106B binding, thereby enhancing TMEM106B-mediated entry (1). ACE2-independent entry was dependent on endogenous TMEM106B, which binds to the receptor binding domain (RBD). Binding is augmented by mutation E484D (3). TMEM106B-specific monoclonal antibodies blocked SARS-CoV-2 infection, demonstrating a role of TMEM106B in viral entry. Using X-ray crystallography, cryogenic electron microscopy (cryo-EM), and hydrogen-deuterium exchange mass spectrometry (HDX-MS), shows that the luminal domain (LD) of TMEM106B engages the receptor-binding motif of SARS-CoV-2 spike (1). The large loop (RBD@471-491) could anchor TMEM106B, which was then firmly locked by another loop (RBD@444-451) (2). TMEM106B also promotes spike-mediated syncytium formation, suggesting a role of TMEM106B in viral fusion. Findings have identified an ACE2-independent SARS-CoV-2 infection mechanism that involves cooperative interactions with the receptors heparan sulfate and TMEM106B (1).

1. Baggen et al., 2023, Cell 186, 3427–3442.
2. Xiaoyu et al., 2024 Jan 25, J Phys Chem Lett. 15(3), 671-680.
3. Prerna et al., 2025, Jan 10;99(2).