Overview:

p29 ING4 is a tumor suppressor protein similar to ING1 that  may inhibit tumor progression by modulating the transcriptional output of signaling pathways which regulate cell proliferation. p29 ING4 has been shown to suppress brain tumor angio-genesis through transcriptional repression of RelA/ NFKB3 target genes when complexed with RelA.  p29 ING4 may also specifically suppress loss of contact inhibition elicited by activated oncogenes such as MYC. p29 ING4 shows a nuclear localization and interacts with EP300, TP53, RelA, inhibits cell growth, and induces apoptosis. This protein contains a PHD-finger, which is a common motif in proteins involved in chromatin remodeling. Multiple alternatively spliced transcript variants have been observed.  The accession number listed below is for variant (1) that encodes the longest isoform.

References:

1. Shiseki,M., et al.: p29ING4 and p28ING5 bind to p53 and p300, and enhance p53 activity. Cancer Res. 2003: 63 (10); 2373-2378.

2. Zhang,X., et al.: ING4 induces G2/M cell cycle arrest and enhances the chemosensitivity to DNA-damage agents in HepG2 cells. FEBS Lett. 2004: 570 (1-3); 7-12.

3. Garkavtsev,I., et al.: The candidate tumour suppressor protein ING4 regulates brain tumour growth and angiogenesis. Nature. 2004: 428 (6980); 328-332.