Ultra-LEAF™ Purified anti-human NRG1b-EGF Antibody, W17087B,BioLegend,638654

Neuregulin 1 (NRG1) was initially identified in the conditioned medium of a human breast tumor cell line as a protein of 45 kD, which induces the phosphorylation of a tyrosine kinase (ERBB2). The neuregulin family includes four members (NRG1-NRG4) that are encoded from four individual genes. Through differential promoter usage and splicing, these members generate 12 isoforms. The best characterized is neuregulin 1, which includes eight isoforms; all isoforms contain (from N-terminus to C-terminus) an immunoglobulin-like (Ig) domain, a growth factor-like domain (EGF), a transmembrane (TM), and a cytoplasmic domain. Alternative splicing in the EGF-like domain of neuregulin 1 results in α and β isoforms. The EGF-like domain is necessary and sufficient for neuregulin bioactivity. The EGFR family of receptors includes four members (ErbB1 through ErbB4), and neuregulins bind to the ErbB3 and ErbB4 receptors. Neuregulins are released from the membrane by proteolytic cleavage, and this process is required for the binding of the neuregulin derived fragments to ErbB receptors. The neuregulin1-β isoform is predominant in the central nervous system and participates in development, survival, and metabolism in neuron and glial cells. Neuregulin1-β is neuroprotective and attenuates inflammatory responses induced by ischemic stroke in rats, preventing macrophage and microglial infiltration and astrocytic activation. Also, neuregulin1-β blocks the induction of pro-inflammatory and stress genes provoked by ischemia. Neuregulins 1-4 are expressed in approximately 25% of breast cancer carcinomas and increase breast cancer cell proliferation, increase tumorigenesis, and promote invasive characteristics of cancer cells. In this sense, neuregulin1-β induces MMP-1 and MMP-9 in cancer cell lines.