EN
HTLV-I virus is as etiological agent of adult T-cell leukemia (ATL).The virus encodes Tax regulatory protein, which induces malignant transformation of the T lymphocytes.Tax increases the expression of cell protooncogenes as well as lymphokines, among others IL-2 and its receptor.This protein induces autocrine proliferation of T lymphocytes, which is probably the main cause of their transformatn.Tax represses the human beta-polymerase gene enzyme involved in host cell DNA repair, and then inversible damage is effected in the T lymphocyte genome.Moreover, this regulatory protein cooperates with Rex phosphoprotein, stabilizing cell mRNA, which originate as the result of Tax protein activity.The regulatory proteins of HTLV-I virus influence the transcription of some genes their products and this way induce malignant transformation.