Tada2b, also known as Ada2beta, is a subunit of the chromatin-modifying complex SAGA. It is involved in multiple biological processes such as pluripotency maintenance, cell survival, growth, and lineage specification in human embryonic stem cells [3]. Tada2b is part of the histone acetyltransferase (HAT) module in SAGA-and ATAC-type co-activators, which is related to histone acetylation, an important epigenetic modification process [5].

In a melanoma model, genome-scale CRISPR-Cas9 knockout screening identified Tada2b as a gene whose loss is involved in resistance to vemurafenib, a therapeutic RAF inhibitor [1]. In the study of histone acetyltransferase KAT2A in human cancer, Protein-Protein Interaction (PPI) analysis indicated that Tada2b levels were negatively correlated with KAT2A expression [2]. Integrated loss-and gain-of-function screens showed that Tada2b is a central regulator in human embryonic stem cell behavior [3]. In an exploratory study on major depressive disorder, increased expression of Tada2b was found in hyperphagic MDD, with significant enrichment of gene ontology pathways mainly related to inflammation [4].

In conclusion, Tada2b plays crucial roles in various biological processes including cancer-related drug resistance, stem cell behavior, and potentially in the pathophysiology of major depressive disorder. The gene knockout-based studies have been instrumental in uncovering these functions, providing valuable insights into disease mechanisms and potential therapeutic targets.