Probable Polycomb group (PcG) protein involved in transcriptional regulation mediated by ligand-bound nuclear hormone receptors, such as retinoic acid receptors (RARs) and peroxisome proliferator-activated receptor gamma (PPARG) (PubMed:16606617). Acts as a coactivator of RARA and RXRA through association with NCOA1 (PubMed:16606617). Acts as a corepressor for PPARG and suppresses its adipocyte differentiation-inducing activity (By similarity). Non- catalytic component of the PR-DUB complex, a complex that specifically mediates deubiquitination of histone H2A monoubiquitinated at 'Lys-119' (H2AK119ub1) (PubMed:20436459, PubMed:30664650, PubMed:36180891). Acts as a sensor of N(6)-methyladenine methylation on DNA (6mA): recognizes and binds 6mA DNA, leading to its ubiquitination and degradation by TRIP12, thereby inactivating the PR-DUB complex and regulating Polycomb silencing (PubMed:30982744). The PR-DUB complex is an epigenetic regulator of gene expression and acts as a transcriptional coactivator, affecting genes involved in development, cell communication, signaling, cell proliferation and cell viability (PubMed:30664650, PubMed:36180891). ASXL1, ASXL2 and ASXL3 function redundantly in the PR-DUB complex (By similarity) (PubMed:30664650). The ASXL proteins are essential for chromatin recruitment and transcriptional activation of associated genes (By similarity). ASXL1 and ASXL2 are important for BAP1 protein stability (PubMed:30664650). Together with BAP1, negatively regulates epithelial-mesenchymal transition (EMT) of trophoblast stem cells during placental development by regulating genes involved in epithelial cell integrity, cell adhesion and cytoskeletal organization (PubMed:34170818). {ECO:0000250|UniProtKB:P59598, ECO:0000269|PubMed:16606617, ECO:0000269|PubMed:20436459, ECO:0000269|PubMed:30664650, ECO:0000269|PubMed:30982744, ECO:0000269|PubMed:34170818, ECO:0000269|PubMed:36180891}. This is the function of Ensembl gene identifier ENSG00000171456 (ASXL1, ASXL transcriptional regulator 1).