NRG1-alpha Protein, Human (HEK293, His)

NRG1-alpha protein acts as a direct ligand for ERBB3 and ERBB4 tyrosine kinase receptors, concurrently recruiting ERBB1 and ERBB2 coreceptors, thereby inducing ligand-stimulated tyrosine phosphorylation and activation of the ERBB receptors. The diverse functions of its multiple isoforms encompass the induction of growth and differentiation in various cell types, including epithelial, glial, neuronal, and skeletal muscle cells. NRG1-alpha is also involved in the expression of acetylcholine receptors during neuromuscular junction formation, the stimulation of lobuloalveolar budding and milk production in the mammary gland, and the induction of differentiation in mammary tumor cells. Furthermore, it stimulates Schwann cell proliferation and plays a role in myocardial development, specifically contributing to the trabeculation of the developing heart. Isoform 10 is implicated in motor and sensory neuron development. NRG1-alpha binds to ERBB4 and ERBB3, acting as a ligand for integrins and forming a ternary complex with integrins and ERBB3, a crucial step in NRG1-ERBB signaling. It induces the phosphorylation and activation of MAPK3/ERK1, MAPK1/ERK2, and AKT1. Additionally, NRG1-alpha participates in ligand-dependent ERBB4 endocytosis, essential for the activation of these kinases in neurons, and interacts with the LIM domain region of LIMK1. It also forms a ternary complex with ERBB3 and integrins ITGAV:ITGB3 or ITGA6:ITGB4 and interacts with NRDC and BACE1.