Proliferation-associated protein 2G4 (PA2G4)

Proliferation-associated protein 2G4 (PA2G4), also known as ErbB3-binding protein 1 (EBP1), is a multifunctional RNA- and DNA-binding protein encoded by the PA2G4 gene. It plays critical roles in growth regulation, RNA processing, ribosome biogenesis, and acts as a transcriptional corepressor of androgen receptor and other cell cycle genes through interaction with histone deacetylases. PA2G4 interacts with several key proteins such as ErbB3, retinoblastoma protein, and Akt, modulating signal transduction, cell cycle progression, and apoptosis. Two main isoforms (p42, p48) exhibit context-dependent and sometimes opposing roles in cancer, functioning as either tumor suppressors or oncogenes in different tissues. PA2G4 is also essential for ciliogenesis by regulating actin meshwork formation and basal body docking in multiciliated cells. Due to its widespread interactions and regulatory functions, PA2G4 is considered a relevant, but complex, therapeutic and prognostic biomarker in cancer and developmental biology[1][2][3][5].

Other names

ErbB3-binding protein 1 (EBP1)ErbB-3 binding protein 1ErbB-3 receptor binding proteinhG4-1ITAF45Cell cycle protein p38-2G4 homologIRES-specific cellular transacting factor 45p38-2G438kDa proliferation-associated 2G4

Modulation of protein-protein interactions (with ErbB3, Rb, HDAC2, androgen receptor). Inhibition/repression of transcription (via HDAC recruitment, Rb interaction). Regulation of translation (IRES-mediated)[2]. Modulation of apoptosis (through AKT and HDM2-p53 pathway)[2]. Interference with signal transduction (primarily through ErbB3 signaling pathways).