Recombinant Mouse TrkA Fc Chimera Protein, CF

Recombinant Mouse TrkA Fc Chimera Protein, CF Summary

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: TrkA

Tropomyocin receptor kinase A (TrkA), also named Neurotrophic tyrosine kinase receptor type 1 (NTRK3) is a member of a nerve growth factor tyrosine kinase receptor family. There are three members of the Trk family, TrkA, TrkB and TrkC, and they bind a group of structurally related, secreted proteins termed neurotrophins, which play an important role in the development and function of the nervous system. The Trk family shares a conserved structural motif consisting of two cysteine-rich domains, a cluster of three leucine-rich motifs, and two immunoglobulin-like domains in the extracellular region, a single transmembrane domain and an intracellular tyrosine kinase domain (3). Natural splice variants of the different Trks, lacking the first cysteine-rich domain, the first and second or all three of the leucine-rich motifs, or the tyrosine kinase domain, have been described (4). Mature mouse TrkA consists of a 383 amino acid (aa) extracellular domain (ECD) which shares 79% and 93% aa identity with human and rat TrkA, respectively. Each Trk family member exhibits different ligand specificities: TrkA binds NGF and NT-3, TrkB binds BDNF, NT-3 and NT-4/5, and TrkC only binds NT-3 (1, 2). The biological activities of the neurotrophins are mediated by binding to and activating two unrelated receptor types: the p75 neurotrophin receptor (p75NTR) and the Trk family receptors (1, 2). P75NTR is a member of the tumor necrosis factor receptor superfamily (TNFRSF) and has been designated TNFRSF16. It binds all neurotrophins with low-affinity to transduce cellular signaling pathways that synergize or antagonize those activated by the Trk receptors. Several TrkA isoforms exist, two of which differ only by a 6-amino acid insertion in their extracellular domain (3). The longer TrkA isoform is the only isoform expressed within neuronal tissues whereas the shorter TrkA is expressed mainly in non-neuronal tissues (3). Trk receptor interactions with NGF play major roles in the development of the sympathetic nervous system, and TrkA, specifically, is essential to the survival of sympathetic neurons in vivo (4). NGF activates retrograde transport of TrkA endosomes for association with actin-modulatory proteins to promote F-actin disassembly, enabling their maturation into transport-competent signaling endosomes (1). Inhibition of the Trk receptors may have several therapeutic implications (5). Injection of a TrkA inhibitor in patients with knee osteoarthritis resulted in sustained pain improvement in a single center trial (6). Another inhibitor showed a significant reduction in psoriatic pruritus, which occurs via a Trka-dependent mechanism (7).

Related Research Areas

• Microglia Homeostasis
• Neurotrophin/Trk Family
• Receptor Tyrosine Kinases (RTKs)
• Receptor Tyrosine Kinases (RTKs) in the Akt Pathway
• VPS10P-domain Family