The function of Ensembl gene identifier ENSG00000153560 (UBP1, upstream binding protein 1) is as follows. Functions as a transcriptional activator in a promoter context-dependent manner. Modulates the placental expression of CYP11A1. Involved in regulation of the alpha-globin gene in erythroid cells. Activation of the alpha-globin promoter in erythroid cells is via synergistic interaction with TFCP2 (By similarity). Involved in regulation of the alpha-globin gene in erythroid cells. Binds strongly to sequences around the HIV-1 initiation site and weakly over the TATA- box. Represses HIV-1 transcription by inhibiting the binding of TFIID to the TATA-box. {ECO:0000250, ECO:0000269|PubMed:10644752, ECO:0000269|PubMed:2006421, ECO:0000269|PubMed:8114710}.