ERBB4 (Erb-B2 Receptor Tyrosine Kinase 4): ERBB4 is a member of the epidermal growth factor receptor (EGFR) family that acts as a key regulator in multiple cellular processes. This transmembrane receptor tyrosine kinase plays an essential role in signaling pathways that control cell proliferation, differentiation, and survival. Beyond these cellular functions, ERBB4 also influences organ development, synaptic plasticity, and cardiac function. Activation of ERBB4 initiates downstream signaling cascades that affect gene expression and cellular behavior, contributing to tissue homeostasis and development. Dysregulation of ERBB4 has been linked to various diseases, including cancer, neurological disorders, and heart abnormalities.