Inhibitor of growth protein 4 (Ing4)

Component of the HBO1 complex that has a histone H4- specific acetyltransferase activity, a reduced activity toward histone H3 and is responsible for the bulk of histone H4 acetylation in vivo. Through chromatin acetylation it may function in DNA replication.

May inhibit tumor development by regulating the transcriptional output of signaling pathways that regulate cell proliferation. Can suppress brain tumor angiogenesis through transcriptional repression of RELA/NFKB3 target genes when complexed with RELA.