i.Regulation of HIV transcription and mechanisims of latency. ii.viral – host interactions. iii.Use of lentiviruses for targeting specific cells for gene therpy application. Dan Levy - Role of SETD6 in modulating HIV latency. Alon Freidman – Targeting of lentiviruses to specific cells. Lost in transcription – mechanisms that drive HIV latency Ongoing Projects Ongoing Collaborations

The Problem - latency is a block for HIV eradication Latency - a reversibly low-productive state of infection, where infected cells retain the capacity to fully re- emerge and produce de-novo viral particles New HIV infections AIDS- related deaths HAART People Total: 34.2 million HIV infected People Latent HIV reservoirs that are refractory to therapy

What are the molecular mechanisms that regulate HIV latency ? Ways to reactivate latent HIV and eliminate viral reservoirs with HAART ? Regulation of HIV transcriptional activation Role of Positive transcription elongation b -PTEFb HYPOTHESIS

NF-AT TAFs… Active State HIV Provirus gag pol tat rev env nef vif vpu vpr 5’LTR Latent State Condensed chromatin HDACs YY1/LSF CBF-1 AP4 NF-AT TAFs… CpG islands met H3K27 me3 SWI/SNF remodeling HIV provirus CCR5/CXCR4 CD4 met P-TEFb HATs HKMT/ SUV39H1 G9a NF-  B Ac 3’LTRAc met nuc1 Ac PRC1/2 Remodeling EZH2 NF-  B A B H3K9 me2 Latency corresponds with transcription activation and chromatin state Open chromatin

HIV Tat - a master switch of viral transcription CDK9 Cyclin T1 LTR RNA Polymerase II P P P P P-TEFb HIV Tat TAR

Recruitment modes of P-TEFb to the viral promoter

PKC activators (Bryostatin, Prostratin) HDAC inhibitors ( SAHA) Bromodomain and extra-terminal (BET) bromodomain inhibitors (JQ1, I- BET) Hypertrophic or stress signals (UV), TCR ligation (IL-2/CD3 Ab) HIV infection Tat Brd4 MePCE LARP7 CycT1 Cdk9 HEXIM1 5’5’ 7SK snRNA P P T270 S278 Ub CycT1 Cdk9 Active state - free active P- TEFb Resting stat - inactive P-TEFb P T186 Cdk9 CycT1 P P Ac K380;386;390;404 P13K/ Akt 3’3’ P-TEFb equilibrium in cells modulates HIV latency

What are the molecular mechanisms that regulate HIV latency ? Ways to reactivate latent HIV and eliminate viral reservoirs ? Role of P-TEFb in establishment of HIV latency Mechanisms that promote viral gene activation identification of host factors that modulate HIV latency Regulation of Transcriptional activation Role of chromatin modulation (collaboration of D.Levy) Screen for small molecules that can reactivate latent HIV Modes of recruitment of P- TEFb to the viral promoter. 4