Abl interactor 1 (ABI1) (ABI1)

Abl interactor 1 (ABI1) is a multifunctional adaptor and scaffold protein that plays a critical role in the regulation of the actin cytoskeleton, cellular morphogenesis, and signal transduction. It is a central component of several macromolecular complexes, including the WAVE regulatory complex (WRC) and the EPS8/SOS1/ABI1 complex, which coordinate Ras-to-Rac signaling to drive membrane protrusion and cell migration. In clinical oncology, ABI1 is recognized as a significant therapeutic target; its dysregulation, often through overexpression or hyperphosphorylation by non-receptor tyrosine kinases like BCR-ABL, is a key driver of metastasis and drug resistance in leukemias and solid tumors such as breast and pancreatic cancer. Beyond malignancy, ABI1 is involved in the pathogenesis of abdominal aortic aneurysms and the regulation of inflammatory responses via TAK1 signaling. While its activity is indirectly managed in the clinic through ABL1 inhibitors like imatinib, specialized inhibitors such as PROTACs and peptides targeting ABI1-mediated signaling complexes are currently in preclinical development to more precisely target its oncogenic functions.

Other names

Abl interactor 1Spectrin SH3 domain-binding protein 1Eps8-binding proteinABI-1SSH3BP1E3B1Abl-binding protein 4 (AbBP4)Nap1-binding protein (Nap1BP)

Inhibition of ABL1/BCR-ABL kinase activity to prevent ABI1 phosphorylation; targeted protein degradation via PROTACs; disruption of ABI1-containing macromolecular signaling complexes such as WAVE2 or SOS1/EPS8/ABI1.