ERBB4

ERBB4 also known as v-erb-a erythroblastic leukemia viral oncogene homolog 4 is a protein that in humans is encoded by the ERBB4 gene. ERBB4 is a member of the Epidermal Growth Factor Receptor (EGFR) family, which is part of the Receptor Tyrosine Kinase (RTK) superfamily. The EGFR family consists of four members: EGFR (also known as ERBB1), ERBB2 (also known as HER2/neu), ERBB3 (also known as HER3), and ERBB4 (also known as HER4). These receptors play critical roles in various cellular processes, including cell proliferation, differentiation, and survival, and have been implicated in the development and progression of many types of cancer.

Function

ERBB4 functions as a receptor for the neuregulins, NRG1 and NRG2, and other ligands such as betacellulin. Upon ligand binding, ERBB4 undergoes homodimerization or heterodimerization with other EGFR family members, leading to the activation of several signal transduction pathways, including the PI3K/AKT pathway, the MAPK pathway, and the Phospholipase C (PLC) pathway. These pathways are involved in regulating various cellular responses such as gene expression, cell growth, and apoptosis.

Clinical Significance

Alterations in the ERBB4 gene, including mutations and overexpression, have been associated with several types of cancer, including breast cancer, ovarian cancer, and melanoma. ERBB4 has been identified as a potential therapeutic target, and drugs that specifically target ERBB4 or its downstream signaling pathways are being developed and tested in clinical trials.

In addition to its role in cancer, ERBB4 signaling is important for heart development and function, and mutations in the ERBB4 gene have been linked to congenital heart defects. ERBB4 is also involved in the development and function of the nervous system, including neuronal survival, synapse formation, and neurotransmitter release.

Genetics

The ERBB4 gene is located on the long arm of chromosome 17 (17q12). It consists of multiple exons that can undergo alternative splicing, resulting in various isoforms of the ERBB4 protein that differ in their cytoplasmic domains and have different biological activities.

See Also

• Epidermal Growth Factor Receptor
• Cancer
• Signal transduction
• Receptor Tyrosine Kinase