en 30800245 <p>Background: Tax-1 protein of Human T-cell Leukemia Virus type 1(HTLV-1) serves as a key transcriptional regulatory gene product and has a crucial role in transactivating genes of infected cells by employing their transcriptional factors. This modulation includes induction of genes which encode CC-chemokines and their receptors. In this study, a recombinant vector containing Tax-1 gene was made and tested for its ability to induce CCR5 (CC chemokine receptor 5) expression in K562 cell line.<br /> Methods: In order to perform this research, two blood samples of HTLV-1 positive were obtained from Urmia blood transfusion center. After DNA extraction, a complete sequence of <em>Tax-1</em> gene was amplified by specific primers. Recombinant vectors carrying Tax-1 gene were synthesized and transformed into <em>Escherichia coli (E. coli)</em>. After bacteria transformation, bacteria containing recombinant plasmid were selected and purified. Then, the recombinant shuttle vectors, <em>pCDNA3.1-TAX</em>, were transfected into the cell culture (K562 cell line). Expression of <em>CCR5</em> was measured after 72 <em>hr</em> by Syber Green Real-Time PCR method compared to control cell culture. Normalization was done with GAPDH as a standard gene.<br /> Results: Cloning of <em>Tax-1</em> gene in the vector, <em>pCDNA3</em>.1 was confirmed by colony PCR, restriction digestion, and sequencing methods. Expression of <em>Tax-1</em> and <em>CCR5</em> genes were confirmed by real time PCR and also, expression of <em>CCR5</em> gene showed an 8-fold increase in comparison to mock-treated controls (p&lt;0.05).<br /> Conclusion: Our data suggested that recombinant <em>Tax-1</em> may have the enhancing effect on CCR5 expression rate at mRNA levels in K562 cell line. Further studies are necessary to evaluate the effect of<em> pCDNA3.1-TAX</em> on cell surface CCR5 expression.</p> CCR5, Human T-cell Leukemia Virus, Tax-1 protein 67 71 https://www.ajmb.org/En/Article.aspx?id=10354 https://www.ajmb.org/PDF/En/FullText/10354.pdf NasrinHaghnazari SadaghianiBlood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran11394LilaPirayeshfardBlood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran11486AfsanehAghaieBlood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran11475ZohrehSharifiBlood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran640