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Recombinant human FGF-8a protein

QK059

Brand: Qkine

Fibroblast growth factor 8a (FGF-8a) is a member of the FGF family and plays a key role in the regulation of embryogenesis, cellular proliferation, differentiation, and migration. FGF-8a is often used for the differentiation of induced pluripotent stem cells, embryonic stem cells, and neural stem cells.

FGF-8a is a spliced form of FGF-8, a heparin-binding protein that targets mammary and non-mammary cells expressing the FGF receptors. A 21.3 kDa highly pure, bioactive recombinant protein produced in an animal-free expression system. This protein is animal-origin free (AOF), carrier protein-free, tag-free, and non-glycosylated to ensure a pure homogenous protein with exceptional lot-to-lot consistency. Qk059 is suitable for enhanced reproducibility and physiologically relevant cultures.

Currency: 

Product name Catalog number Pack size Price Price (USD) Price (GBP) Price (EUR)
Recombinant human FGF-8a protein, 25 µg QK059-0025 25 µg (select above) $ 210.00 £ 155.00 € 182.00
Recombinant human FGF-8a protein, 50 µg QK059-0050 50 µg (select above) $ 315.00 £ 255.00 € 265.00
Recombinant human FGF-8a protein, 100 µg QK059-0100 100 µg (select above) $ 500.00 £ 375.00 € 438.00
Recombinant human FGF-8a protein, 500 µg QK059-0500 500 µg (select above) $ 1,995.00 £ 1,475.00 € 1,723.00
Recombinant human FGF-8a protein, 1000 µg QK059-1000 1000 µg (select above) $ 3,100.00 £ 2,300.00 € 2,687.00

Note: prices shown do not include shipping and handling charges.

Qkine company name and logo are the property of Qkine Ltd. UK.

Alternative protein names
AIGF, AIGFKAL6, Androgen-induced growth factor, FGF8, FGF-8, Fibroblast Growth Factor – 8, HBGF-8, Heparin Binding Growth Factor – 8, MGC149376
Species reactivity

human

species similarity:
mouse – 100%
rat – 100%
porcine – 100%
bovine – 100%

Frequently used together:

Summary

  • High purity human FGF-8a protein (Uniprot: P55075-2)
  • 21.3 kDa
  • >98%, by SDS-PAGE quantitative densitometry
  • Expressed in E. coli
  • Animal origin-free (AOF) and carrier protein-free
  • Manufactured in Qkine's Cambridge, UK laboratories
  • Lyophilized from HEPES, NaCl, mannitol
  • Resuspend in sterile-filtered water at >50 µg/ml, add carrier protein if desired, prepare single use aliquots and store frozen at -20 °C (short-term) or -80 °C (long-term).
Handling and Storage FAQ

Featured applications

  • Differentiation of midbrain dopaminergic neurons
  • Neurite outgrowth from spiral ganglion neurons
  • Morphogenesis of mid-hindbrain
  • Differentiation of iPSC derived neural progenitors to neurons

Bioactivity

FGF-8a activity was determined using the Promega serum response element luciferase reporter assay (*) in HEK293T cells. EC50 = 110 ng/ml (5.2 nM). Cells were treated in triplicate with a serial dilution of FGF-8a in the presence of 10 µg/ml heparin for 3 hours. Firefly luciferase activity was measured and normalized to the control Renilla luciferase activity. Data from Qk059 lot #104406. *Promega pGL4.33[luc2P/SRE/Hygro] #E1340

Qk059-FGF-8a-bioactivity

Purity

FGF-8a (Qk059) migrates as a single band at 21.3 kDa in non-reducing (NR) conditions and upon reduction (R). Purified recombinant protein (3 µg) was resolved using 15% w/v SDS-PAGE in reduced (+β-mercaptothanol, R) and non-reduced (NR) conditions and stained with Coomassie Brilliant Blue R250. Data from Qk059 batch #104412.

human-mouse-FGF-8a-Qk059-protein-purity-lot-104406-1024x1024

Further quality assays

  • Mass spectrometry: single species with expected mass
  • Recovery from stock vial:  >95%
  • Endotoxin: <0.005 EU/μg protein (below level of detection)

Qk059-FGF-8a-comparison-bioactivity

Qkine animal origin-free FGF-8a is more biologically active than mammalian-origin comparable alternative. Quantitative luciferase assay with Qkine FGF-8a (Qk059, green) and alternative supplier FGF-8a (Supplier B, black). Cells were treated in triplicate with a serial dilution of FGF-8a for 3 hours in the presence of 10 µg/ml heparin. Firefly luciferase activity was measured and normalized to control Renilla luciferase activity.

Protein Background

FGF-8a is a heparin-binding protein and an isoform of FGF-8 belonging to a family of fibroblast growth factors (FGF) [1]. It was originally discovered as an essential growth factor for the androgen-dependent growth of mouse mammary carcinoma cells [2]. In mouse, there are eight spliced protein isoforms of FGF8 (a-h) whereas, in humans, there are four alternate spliced protein isoforms namely FGF-8a, FGF-8b, FGF-8e, and FGF-8f. These four FGF8 isoforms (a, b, e and f) are highly conserved between humans and mice. Human and murine FGF-8a and FGF-8b show 100% homology [3] whereas there is a 98% identity with human and murine FGF8e and FGF8f [4]. Human FGF-8a, a monomeric protein has a molecular weight of 21.3kDa with 182 amino acid (aa) residues covering the signal sequence domain, N-terminal domain, FGF domain and proline-rich C terminal sequence [5]. Its three-dimensional structure is composed of two antiparallel beta-sheet and several alpha-helices. The protein contains a conserved heparin-binding domain that is essential for its biological activity. This domain binds to heparin sulfate proteoglycans on the cell surface and helps to localize FGF8a to its target cells.

FGF-8, including the spliced forms, functions by binding the FGF receptors (FGFR) to activate the Ras/MAPK signaling pathway, a key pathway that contributes to several cellular processes. In general, the FGF family is involved in broad cellular and biological processes including cell proliferation, differentiation, survival, and apoptosis [6-8].

Functionally, FGF-8a has been shown to play a major role during prenatal development. It is widely expressed during embryogenesis and is a key player in epithelial-mesenchymal transitions [9]. During gastrulation, it contributes to the organization and induction role and regulates the patterning of organs in the embryos. These organs include the brain, eye, ear, limb, and heart [10-12].

Although, FGF-8 isoforms work in a coordinated and concerted manner, findings have suggested that they also have distinct key roles. FGF-8a is required for morphogenesis and neurogenesis [13]. A study using transgenic mice showed FGF-8a expands the midbrain while FGF-8b showed a transformational activity by transforming the midbrain into the cerebellum [10].

Furthermore, FGF-8a has been used to generate embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs)-derived ventral midbrain dopaminergic (DA) neurons [14]. FGF-8a has also been shown to play a role in neuronal induction during neural development and neurite outgrowth from spiral ganglion neurons in vitro [15-16].

Whilst there is limited expression of FGF-8 and its isoforms in the normal adult, increasing studies have shown the presence of FGF-8 in adult tissues and cells including the reproductive tract, peripheral leukocytes, and hematopoietic cells [17-19]. Further functional studies are required to fully delineate the role of FGF-8 and its isoforms in the normal adult.

Background references

  1. Belov AA and Mohammadi M: Molecular mechanisms of fibroblast growth factor signaling in physiology and pathology. Cold Spring Harb Perspect Biol. 5:5 (2013).doi: 10.1101/cshperspect.a015958
  2. Liu R, Huang S, Lei Y, Zhang T, Wang K, Liu B, Nice EC, Xiang R, Xie K, Li J, et al: FGF8 promotes colorectal cancer growth and metastasis by activating YAP1. Oncotarget. 6:935–952 (2015).doi: 10.18632/oncotarget.2822
  3. Katoh M and Katoh M: Comparative genomics on FGF8, FGF17, and FGF18 orthologs. Int J Mol Med. 16:493–496 (2005).doi.org/10.3892/ijmm.16.3.493
  4. Gemel J, Gorry M, Ehrlich GD and MacArthur CA: Structure and sequence of human FGF8. Genomics. 35:253–257 (1996).doi: 10.1006/geno.1996.0349
  5. Reuss, Bernhard, and Oliver von Bohlen und Halbach. “Fibroblast growth factors and their receptors in the central nervous system.” Cell and tissue research. 313(2): 139-57 (2003).doi: 10.1007/s00441-003-0756-7
  6. Sternberg PW and Alberola-Ila J: Conspiracy theory: RAS and RAF do not act alone. Cell. 95:447–450 (1998).doi: 10.1016/s0092-8674(00)81612-8
  7. Thisse B, Thisse C. Functions and regulations of fibroblast growth factor signaling during embryonic development Dev Biol. 287(2):390-402 (2005).doi: 10.1016/j.ydbio.2005.09.011
  8. Turner N and Grose R: Fibroblast growth factor signalling: From development to cancer. Nat Rev Cancer. 10:116–129 (2010).doi: 10.1038/nrc2780
  9. Jaskoll T, Witcher D, Toreno L, Bringas P, Moon AM and Melnick M: FGF8 dose-dependent regulation of embryonic submandibular salivary gland morphogenesis. Dev Biol. 268:457–469 (2004).doi:10.1016/j.ydbio.2004.01.004
  10. Olsen SK, Li JY, Bromleigh C, Eliseenkova AV, Ibrahimi OA, Lao Z, Zhang F, Linhardt RJ, Joyner AL and Mohammadi M: Structural basis by which alternative splicing modulates the organizer activity of FGF8 in the brain. Genes Dev. 20:185–198 (2006).doi: 10.1101/gad.1365406
  11. Crossley PH, Minowada G, MacArthur CA, Martin GR. Roles for FGF8 in the induction, initiation, and maintenance of chick limb development. Cell. 84(1):127-136 (1996). doi: 10.1016/s0092-8674(00)80999-x
  12. Heikinheimo M, Lawshé A, Shackleford GM, Wilson DB, MacArthur CA. Fgf-8 expression in the post-gastrulation mouse suggests roles in the development of the face, limbs and central nervous system. Mech Dev. 48(2):129-138 (1994).doi: 10.1016/0925-4773(94)90022-1
  13. Leerberg DM, Hopton RE, Draper BW. Fibroblast Growth Factor Receptors Function Redundantly During Zebrafish Embryonic Development. Genetics. 212(4):1301-1319 (2019).doi: 10.1534/genetics.119.302345
  14. Cooper O, Hargus G, Deleidi M, et al. Differentiation of human ES and Parkinson’s disease iPS cells into ventral midbrain dopaminergic neurons requires a high activity form of SHH, FGF8a and specific regionalization by retinoic acid. Mol Cell Neurosci. 45(3):258-266 (2010).doi: 10.1016/j.mcn.2010.06.017
  15. García-Hernández S, Potashner SJ, Morest DK. Role of fibroblast growth factor 8 in neurite outgrowth from spiral ganglion neurons in vitro. Brain Res. 1529:39-45 (2013).doi: 10.1016/j.brainres.2013.07.030
  16. Hulstrand AM, Houston DW. Regulation of neurogenesis by Fgf8a requires Cdc42 signaling and a novel Cdc42 effector protein. Dev Biol. 382(2):385-399 (2013).doi: 10.1016/j.ydbio.2013.08.020
  17. Payson RA, Wu J, Liu Y, Chiu IM. The human FGF-8 gene localizes on chromosome 10q24 and is subjected to induction by androgen in breast cancer cells. Oncogene.13(1):47-53 (1996).PMID: 8700553
  18. Ghosh AK, Shankar DB, Shackleford GM, et al. Molecular cloning and characterization of human FGF8 alternative messenger RNA forms. Cell Growth Differ. 7(10):1425-1434 (1996).PMID: 8891346
  19. Nezu M, Tomonaga T, Sakai C, et al. Expression of the fetal-oncogenic fibroblast growth factor-8/17/18 subfamily in human hematopoietic tumors. Biochem Biophys Res Commun. 335(3):843-849 (2005).doi: 10.1016/j.bbrc.2005.07.153