Recombinant human/ bovine/ porcine NRG-1 protein

Summary

• High purity human NRG-1 protein (Uniprot: Q02297)
• 7.5 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 acetonitrile, TFA
• 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).

Featured applications

• Maintenance of pluripotency in human iPSC

NRG-1 activity is determined using the Promega serum response element luciferase reporter assay (*) in transfected MCF-7 cells. Cells are treated in triplicate with a serial dilution of NRG-1 for 4 hours. Firefly luciferase activity is measured and normalized to the control Renilla luciferase activity. EC50 = 37.9 pM (0.28 ng/mL). Data from Qk045 lot #104317. *Promega pGL4.33[luc2P/SRE/Hygro] #E1340

NRG-1 migrates as a single band at 7.5 kDa in non-reducing (NR) conditions and upon reduction (R).  No contaminating protein bands are visible. Purified recombinant protein (3 µg) was resolved using 18% w/v SDS-PAGE in reduced (+β-mercaptothanol, R) and non-reduced (NR) conditions and stained with Coomassie Brilliant Blue R250.  Data from Qk045 batch #104317.

Protein background

Neuregulin 1 (NRG-1) is a member of the neuregulin family (along with NRG 2-4). Each member of this family is encoded by an individual gene.  Alternative splicing and different promoter utilisation results in a large number of isoforms for each member of the protein family – for example, NRG-1, the best studied member, generates six types of protein (I–VI) and at least 31 isoforms [1]. These isoforms have different tissue distribution, potency, receptor specificity and biological functions [2].

All NRG-1 isoforms contain the bioactive EGF-like domain, this EGF-like domain has two isoforms: alpha and beta. These differ in their receptor affinity; both the alpha and beta isoforms are ligands for the receptors ErbB3 (HER3) and ErbB4 (HER4), however the NRG-1 beta isoform has a higher affinity for the ErbB4 receptor than the alpha isoform [3]. This protein (Qk045) consists of the β isoform of the EGF domain of NRG-1 protein.

NRG-1 has an essential role in cardiac and neuronal development, and is implicated in disorders such as schizophrenia [4], and numerous cancers, for example breast cancer where NRG-1 promotes the proliferation and migration of breast cancer cells [5]. In cell culture, NRG-1 is frequently used in maintenance media for human pluripotent stem cells and other cells.

Background references

1. Mei, Lin, and Wen-Cheng Xiong. ‘Neuregulin 1 in Neural Development, Synaptic Plasticity and Schizophrenia’. Nature Reviews Neuroscience, vol. 9, no. 6, June 2008, pp. 437–52. doi.org/10.1038/nrn2392.
2. Breuleux, M. ‘Role of Heregulin in Human Cancer’. Cellular and Molecular Life Sciences, vol. 64, no. 18, Sept. 2007, pp. 2358–77. doi.org/10.1007/s00018-007-7120-0.
3. Hobbs, Stuart S., et al. ‘Neuregulin Isoforms Exhibit Distinct Patterns of ErbB Family Receptor Activation’. Oncogene, vol. 21, no. 55, Dec. 2002, pp. 8442–52. doi.org/10.1038/sj.onc.1205960.
4. Shi, Liang, and Clare M. Bergson. ‘Neuregulin 1: An Intriguing Therapeutic Target for Neurodevelopmental Disorders’. Translational Psychiatry, vol. 10, no. 1, June 2020, pp. 1–11. doi.org/10.1038/s41398-020-00868-5.
5. Berdiel-Acer, Mireia, et al. ‘Stromal NRG1 in Luminal Breast Cancer Defines Pro-Fibrotic and Migratory Cancer-Associated Fibroblasts’. Oncogene, vol. 40, no. 15, Apr. 2021, pp. 2651–66. doi.org/10.1038/s41388-021-01719-3.

Publications using Recombinant human NRG-1 protein (Qk045)

Refined home-brew media for cost-effective, weekend-free hiPSC culture and genetic engineering
Truszkowski L, Bottini S, Bianchi S et al.
DOI: https://doi.org/10.12688/openreseurope.18245.1