The neuregulin family of structurally related glycoproteins comprises products from four distinct but related genes, Nrg-1, Nrg-2, Nrg-3, and Nrg-4. Through alternative splicing or the use of alternative promoters, Nrg-1 has been shown to encode more than 14 soluble or transmembrane proteins. The extracellular domain of the transmembrane NRG1 isoforms can be proteolytically cleaved to release soluble growth factors. All NRG1 isoforms contain an EGF-like domain ( alpha - or beta -splice variant that differ in their C-terminal region) that is required for their direct binding to the ErbB3 or ErbB4 receptor tyrosine kinases. The ErbB3 or ErbB4 subsequently recruits and heterodimerizes with ErbB2, resulting in tyrosine phosphorylation and NRG1 signaling. NRG1 isoforms can be classified into three major subtypes. Type I (Neu Differentiation Factor, NDF; Heregulin, HRG; Acetylcholine Receptor Inducing Activity, ARIA) and type II (Glial Growth Factor, GGF) NRG1s have an immunoglobulin (Ig)-like domain N-terminal to the EGF-like domain. Type I NRG1s differ from type II NRG1s by having a glycosylation-rich domain between the Ig-like and the EGF-like domains. Type III NRG1s (Sensory and Motor neuron-Derived Factor) lacks the Ig-like domain but has a cysteine rich domain (CRD) instead. NRG1 isoforms show distinct spatial and temporal expression patterns. These proteins play important roles during development of both the nervous system and the heart. They have been shown to regulate the selective expression of neurotransmitter receptors in neurons and at the neuromuscular junction, and promote the differentiation and development of Schwann cells from neural crest stem cells. NRG1s have also been shown to be involved in the establishment of the oligodendroglial lineage. Product Properties Synonyms ARIA; GGF; GGF2; HGL; HRG; Neuregulin-1 beta 1; NRG1 beta 1 Accession Q02297 GeneID 3084 Source E.coli-derived Human NRG1-β1, Ser177-Glu241. Molecular Weight Approximately 7.5 kDa. AA Sequence SHLVKCAEKE KTFCVNGGEC FMVKDLSNPS RYLCKCPNEF TGDRCQNYVM ASFYKHLGIE FMEAE Tag None Physical Appearance Sterile Filtered White lyophilized (freeze-dried) powder. Purity > 97 % by SDS-PAGE and HPLC analyses. Biological Activity The ED50 as determined by a cell proliferation assay using serum free human MCF-7 cells is less than 0.5 ng/mL, corresponding to a specific activity of > 2.0 × 106 IU/mg. Fully biologically active when compared to standard. Endotoxin < 0.1 EU per 1μg of the protein by the LAL method. Formulation Lyophilized from a 0.2 μm filtered solution in 1 × PBS, pH 7.4, with 5 % trehalose. Reconstitution We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20℃. Further dilutions should be made in appropriate buffered solutions. Shipping and Storage The products are shipped with ice pack and can be stored at -20℃ for 1 year. 1 month, 2 to 8 °C under sterile conditions after reconstitution. 3 months, -20 to -70 °C under sterile conditions after reconstitution. Recommend to aliquot the protein into smaller quantities when first used and avoid repeated freeze-thaw cycles. Cautions 1.Avoid repeated freeze-thaw cycles. 2.For your safety and health, please wear lab coats and disposable gloves for operation. 3.For research use only! Documents Manual
