Jurkat control vs J Tat72

1. HIV-1 Tat protein up-regulates human cellular miRNAs involved in T cell apoptosis and cell cycle regulation: requirement of Tat second exon INTRODUCTION RESULTS microRNA array Confirmation by qRT-PCR We observe that… 1- HIV-1 Tat does not show RNAi suppressor activity 2- Tat specifically dysregulates some cellular miRNAs 3- These changes are dependent on the second exon of Tat Fold change Triplicate Triplicate Jurkat control vs J Tat101 Jurkat control vs J Tat72

2. Up-regulation of cellular miR-21 by Tat and its implication in apoptosis The precursor of miR-21 is also increased miR-21 targets are down-regulated Fold change Fold change These proteins have pro-apoptotic effects % Annexin-V Increased resistance to apoptosis in Jurkat Tat101 High levels of miR-21 correlates to the increase of the anti-apoptotic protein Bcl-2 J Control J Control J Tat101 J Tat101 J Tat72 J Tat72 FasL 4h - - - + + + Bcl-2 -actin

3. Up-regulation of cellular miR-222 by Tat and its relation to cell cycle progression The precursor of miR-222 is also increased miR-222 target is down-regulated CDKN1B inhibits cell cycle progression at G1 phase Fold change Fold change G1/S phases: 53,60 % Increased activation of cell cycle in Jurkat Tat101 at G1 and early S phases G1/S phases: 21,45 % Conclusions • HIV-1 Tat does not show RNAi suppressor activity, but it specifically up-regulates miR-21 and miR-222 and their precursors and down-regulates miR-128 • These modifications are dependent on the second exon of Tat. • Targets of the enhanced miRNAs are down-regulated. This could explain the specific phenotype of resistance to apoptosis and cell cycle activation observed in Jurkat Tat101. Events Propidium iodide Propidium iodide Propidium iodide Jurkat control Jurkat Tat72 Jurkat Tat101 Acknowledgements G1/S phases: 20 %