BCR-Abl

Molecular biology

The normal BCR gene is ubiquitously expressed cytoplasmic protein with many known functionalities. ABL1 gene expresses a membrane-associated protein, a nonreceptor protein-tyrosine kinase. ABL1 is linked to multiple processes related to cell growth and survival, such as cytoskeleton and actin remodelling, and inhibition of cell cycle progression. ABL1 can also be found translocated in the nucleus and has DNA binding capabilities, as it is involved in DNA damage control and repair, and apoptosis. The BCR-ABL1 transcript is also translated into a tyrosine kinase containing domains from both the BCR and ABL1 genes. The activity of tyrosine kinases is typically regulated in an auto-inhibitory fashion, but the BCR-ABL1 fusion gene codes for a protein that is constitutively activated, leading to impaired DNA binding and unregulated cell division (i.e. cancer).