Recombinant Human Semaphorin 4F Fc Chimera Protein, CF

Recombinant Human Semaphorin 4F 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: Semaphorin 4F

Semaphorin 4F (Sema4F; previously called Sema W) is a 100-150 kDa member of the class 4 family of type I transmembrane semaphorins (1-3). It is expressed in Schwann cells, oligodendrocyte (highest in precursors), retinal ganglion cells, and neurons, especially along migratory pathways (2-4). It is found within post-synaptic densities at glutamatergic synapses, where it binds and probably recruits the cytoplasmic scaffolding protein PSD-95 (3, 5). There are two isoforms of human Sema4F. The short isoform is missing aa 120-274. The canonical long isoform is synthesized as a 770 aa protein that includes a 34 aa signal peptide, a 625 aa extracellular domain (ECD), a 21 aa transmembrane segment, and a 90 aa cytoplasmic tail. The ECD contains a Sema domain, a PSI region, and a C2-type Ig-like domain. Within the ECD, human Sema4F shares 92% aa sequence identity with the mouse and rat Sema4F. Sema4F is expressed at the highest levels postnatally suggesting an important role in nerve system maintenance and repair (2). In Schwann cells, Sema4F acts as an adhesive protein and a mediator of contact inhibition, and thus an inhibitor of Schwann cell proliferation (6). In neurofibromatosis type 1 (NT1), loss of the NF1 protein results in loss of Schwann cell Sema4F expression via perturbation of ERK signals (6). Loss of Sema4F in turn disrupts adhesive interaction and alignment of Schwann cells with neurons (6). For oligodendroglial precursors in culture, immobilized Sema4F inhibits migration and enhances survival, differentiation and adhesion (3). Sema4F is involved in cancer-induced neurogenesis and may serve as a critical regulator of neuro-epithelial interactions and a biomarker of aggressive prostate cancer (7).

Related Research Areas

• Axon Guidance and Neuron Migration
• Proteoglycans
• Semaphorins, Plexin Receptors, and Related Molecules