Autophagy/Beclin 1 Regulator 1 (AMBRA1)

AMBRA1 bound BECN1, a component of the class III phosphatidylinositol-3 kinase complex (VPS34, or PIK3C3;) that regulates autophagosome formation. Downregulation of AMBRA1 expression in a human fibrosarcoma cell line increased autophagy and the rate of cell proliferation. Conversely, overexpression of AMBRA1 decreased autophagy and the rate of cell proliferation. AMBRA1 downregulation also significantly reduced the ability of BECN1 to interact with VPS34.

Ambra1, which encodes a deduced 1,300-amino acid protein with an N-terminal WD40 domain. By database analysis, they identified and cloned human AMBRA1, which encodes a deduced 1,269-amino acid protein. Ambra1 was expressed throughout development in mice, with strong staining in the neuroepithelium.