Recruiter that couples transcriptional factors to general transcription apparatus and thereby modulates transcription regulation and chromatin formation. Can both act as an activator or a repressor depending on the context. Required for HUSH-mediated heterochromatin formation and gene silencing (PubMed:27732843). Mediates MBD1-dependent transcriptional repression, probably by recruiting complexes containing SETDB1 (PubMed:12665582). Stabilizes SETDB1, is required to stimulate histone methyltransferase activity of SETDB1 and facilitates the conversion of dimethylated to trimethylated H3 'Lys-9' (H3K9me3). The complex formed with MBD1 and SETDB1 represses transcription and couples DNA methylation and histone H3 'Lys-9' trimethylation (H3K9me3) (PubMed:14536086, PubMed:27732843). Facilitates telomerase TERT and TERC gene expression by SP1 in cancer cells (PubMed:19106100). Interacts with MBD1; the interaction is enhanced when MBD1 is sumoylated (PubMed:12665582, PubMed:16757475). Interacts with SETDB1; the interaction protects SETDB1 from proteasomal degradation and is required to stimulate histone methyltransferase activity and facilitate the conversion of dimethylated to trimethylated H3 'Lys-9' (PubMed:14536086, PubMed:15691849, PubMed:27732843). Interacts with SUMO ubiquitin-like proteins (SUMO1, SUNO2 and SUMO3), with a preference for SUMO2 and SUMO3 (PubMed:16757475, PubMed:18842587). Interacts with SP1, ATF7 and ZHX1 (PubMed:10976766, PubMed:12659632, PubMed:19106100). Interacts with the general transcription machinery, including ERCC2, ERCC3, GTF2E1, GTF2E2 and POLR2A (PubMed:19106100). (Microbial infection) Interacts with Epstein-Barr virus BRLF1/Rta protein, leading to the regulation of host genes in Epstein-Barr virus-infected cells. Detected at low levels in breast, lung and stomach; highly up-regulated in the corresponding cancerous tissues (at protein level). Belongs to the MCAF family. Contaminating sequence. Potential poly-A sequence. Truncated N-terminus. Intron retention. Truncated N-terminus.