ING5 is a member of the ING family. It is similar to ING1, a tumor suppressor protein that can interact with TP53, inhibit cell growth, and induce apoptosis. ING5 contains 1 PHD-type zinc finger. It can bind TP EP300/p300, a component of the histone acetyl transferase complex, suggesting its involvement in TP53-dependent regulatory pathway. ING5 is a component of the HBO1 complex. HBO1 complex 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. HBO1 complex composed at least of ING4 or ING5, KAT7/HBO1, MEAF6, and one of PHF15, PHF16 and PHF17. ING5 also is a component of the MOZ/MORF complex which is composed at least of ING5, KAT6A, KAT6B, MEAF6 and one of BRPF1, BRD1/BRPF2 and BRPF3. It interacts with EP300 and TP53. MOZ/MORF complex has a histone H3 acetyltransferase activity. Through chromatin acetylation ING5 may regulate DNA replication and may function as a transcriptional coactivator. It interacts with H3K4me3 and to a lesser extent with H3K4me2.