Transcriptional trans-acting proteins of the promoter elements found in the long terminal repeats (LTR) of HUMAN T-LYMPHOTROPIC VIRUS 1 and HUMAN T-LYMPHOTROPIC VIRUS 2. The tax (trans-activator x; x is undefined) proteins act by binding to enhancer elements in the LTR.

Synonyms: p40(tax), pX, Trans-Activator Protein, Trans Activator Protein p40x, Gene Products, tax, tax Gene Products, Trans Activator Protein pX, Antigen p40x, Transforming, p40x, Transforming Antigen, Transactivator Protein p40(x), 0, Trans-Activator Protein p40x, Gene Product, tax, Trans-Activator Protein pX, tax Gene Product, tax Protein, Trans-Activator Protein p40(x), p40x, Trans-Activator Protein, Trans-Activator Protein p40(tax), Trans-Activator Protein p40(lor), Transforming Antigen p40x, Transactivator p40(tax), p40 tax