APBB1
Description
The APBB1 (amyloid beta precursor protein binding family B member 1) is a protein-coding gene located on chromosome 11.
Amyloid beta A4 precursor protein-binding family B member 1 is a protein that in humans is encoded by the APBB1 gene. The protein encoded by this gene is a member of the Fe65 protein family. It is an adaptor protein localized in the nucleus. It interacts with the Alzheimer's disease amyloid precursor protein (APP), transcription factor CP2/LSF/LBP1 and the low-density lipoprotein receptor-related protein. APP functions as a cytosolic anchoring site that can prevent the gene product's nuclear translocation. This encoded protein could play an important role in the pathogenesis of Alzheimer's disease. It is thought to regulate transcription. Also it is observed to block cell cycle progression by downregulating thymidylate synthase expression. Multiple alternatively spliced transcript variants have been described for this gene but some of their full length sequence is not known. APBB1 has been shown to interact with APLP2, TFCP2, LRP1 and Amyloid precursor protein.
APBB1, also known as Fe65, acts as a transcription coregulator, capable of both activating and repressing gene expression. It forms a complex with the intracellular domain of the amyloid precursor protein (APP), playing a key role in cellular responses to DNA damage, including apoptosis. APBB1 binds to phosphorylated histone H2AX at double-strand breaks (DSBs), recruiting pro-apoptotic factors and facilitating histone H4 acetylation at these sites. Furthermore, it associates with chromatin-modifying enzymes such as KAT5/TIP60, contributing to its transcription activation activity. In contrast, APBB1 also represses transcription by interacting with TSHZ3, SET, and HDAC factors, inhibiting CASP4 expression. Beyond transcription regulation, APBB1 is involved in neurite outgrowth, hippocampal neurite branching, and neuromuscular junction formation, influencing spatial memory. It is also implicated in maintaining lens transparency and potentially muscle cell strength. APBB1 acts as a molecular adapter, activating the RAC1-ARF6 axis during insulin treatment to promote neurite outgrowth.
APBB1 is also known as FE65, MGC:9072, RIR.
Associated Diseases
- endometrial cancer
- urinary bladder cancer
- 7q11.23 microduplication syndrome
- microangiopathy and leukoencephalopathy, pontine, autosomal dominant
- schizophrenia
- cancer
- colorectal cancer