Betacellulin

Betacellulin (BTC) is a member of the EGF (Epidermal Growth Factor) family that is found in various tissues including the pancreas and small intestine. It is a mitogen for retinal pigment epithelial cells, vascular smooth muscle cells, and fibroblasts. BTC can also stimulate the growth of hepatocytes and epithelial cells.

Structure

BTC is synthesized as a preproprotein that is processed to generate the mature protein. The mature protein consists of 80 amino acids and shares 44% amino acid sequence identity with EGF.

Function

BTC binds to and activates the EGFR (Epidermal Growth Factor Receptor), leading to the activation of the downstream MAPK (Mitogen-Activated Protein Kinase) and PI3K (Phosphoinositide 3-Kinase) signaling pathways. These pathways regulate cell proliferation, survival, and differentiation.

BTC has been shown to promote the differentiation of pancreatic beta cells, and it may play a role in the development of the pancreas. It has also been suggested that BTC could be used therapeutically to stimulate the regeneration of beta cells in patients with diabetes mellitus.

Clinical significance

Alterations in the expression of BTC have been associated with various cancers, including breast cancer, lung cancer, and colorectal cancer. In these cancers, BTC may act as an autocrine growth factor.

See also

• Epidermal Growth Factor
• Epidermal Growth Factor Receptor
• Mitogen
• Pancreatic beta cells
• Diabetes mellitus

External links

• Betacellulin at UniProt

Betacellulin

• PDB 1ip0 EBI
  PDB 1ip0 EBI
• Wikipedia image2
  Wikipedia image2