Tripartite motif-containing protein 33 (TRIM33)

Tripartite motif-containing protein 33 (TRIM33), also referred to as TIF1-gamma, is a multidomain protein that functions as both a transcriptional co-regulator and an E3 ubiquitin-protein ligase (UniProt: Q9UPN9). It is a critical modulator of the TGF-beta signaling pathway, where it can either promote or inhibit signaling by interacting with SMAD proteins or altering chromatin accessibility (He et al., 2006; Xi et al., 2011). In clinical oncology, TRIM33 often acts as a tumor suppressor, and its loss is associated with the progression of pancreatic cancer and chronic myelomonocytic leukemia (Pommier et al., 2015). However, chromosomal rearrangements resulting in TRIM33-RET fusions serve as oncogenic drivers in subsets of lung and thyroid cancers (Alberti et al., 2005). Because TRIM33 contains a bromodomain and a PHD finger, it serves as an epigenetic 'reader' of histone modifications, making it a viable target for small-molecule inhibitors (Structural Genomics Consortium). Research compounds such as TP-472 target the TRIM33 bromodomain to explore its therapeutic potential in cancer and inflammatory diseases by disrupting its recruitment to specific gene loci (Hatakeyama, 2017).

Other names

Transcription intermediary factor 1-gammaTIF1-gammaRFG7EctoderminPTC7RET-fused gene 7 protein

Bromodomain inhibition (e.g., TP-472), E3 ubiquitin ligase-mediated degradation of SMAD4, or antagonism of SMAD4 binding to SMAD2/3 complexes.