Marina Lusic
Marina Lusic
affiliation: ICGEB, International Centre for Genetic Engineering and Biotechnology, Trieste
research area(s): Molecular Biology, Immunity And Infection
Course: Basic and Applied Immunology
University/Istitution: Università Vita-Salute San Raffaele
12/2003: PhD degree in Molecular Biology and Biochemistry, Faculty of Biological Sciences, University of Belgrade. Thesis "Molecular Analysis of the Changes Following Transcriptional Activation of the HIV-1 LTR promoter"
07/1998: M.Sc. degree in Molecular Biology and Biochemistry, Faculty of Biological Sciences, University of Belgrade Thesis entitled "Analysis of Erythro-specific Isoforms of Protein 4.1 in Belgrade Laboratory (b/b) Rat"
11/1994: B. Sc. degree in Microbiology with vote 10/10 cum laude at the Faculty of Biological Sciences, University of Belgrade. The practical part for the thesis entitled "The Use of Microbiological Tests in Chemical Monitoring of Soil Contaminations" has been performed in Germany, at Fraunhofer Institute

2009-present Extended faculty member, San Rafffaele Scientific Institute, Milan
2006-present Research scientist in Lab of Molecular Medicine, ICGEB, Trieste
6/2004-2006 Post-doctoral scientist in the laboratory of Molecular Medicine: Research project "Nuclear organization, chromatin and regulation of HIV-1 gene expression" Special emphasis on regulation of Eukaryotic RNA Pol II mediated transcription and disease. Involved also in a project "HIV-1 Integrase and its cellular partners"; supervision of the work of several pre-doctoral students
1/2004-6/2004: Six months maternity leave
3/2000-12/2003: Research fellow in the Molecular Medicine Laboratory, supervised by Prof Dr Mauro Giacca. Project description regulation of HIV-1 gene expression: chromatin modification and factor recruitment at the LTR Promoter
6/1999- 3/2000: Molecular Medicine Laboratory, International Centre for Genetic Engineering and Biotechnology (head Prof. Mauro Giacca). Involved in a project "Identification and characterization of new human DNA replication origins" as a guest scientist.
12/1994-7/1998 Graduate student, financed by Serbian Ministry of Science and Technology in the Laboratory for Molecular Haematology at the Institute of Molecular Genetics and Genetic Engineering in Belgrade. Studies on mRNA splicing patterns, protein synthesis and protein-protein interactions of membrane proteins were performed under the supervision of dr Zvezdana Popovic, laboratory head and Prof. Vladimir Glisin, director of IMGGE
1993: Undergraduate student in the Laboratory for Microbiology of the Soil, supervised by dr Kerstin Hund-Rinke, at the Fraunhofer Institute fur Molekularbiologie und Angewandte Ecologie (Molecular Biology and Applied Ecology) in Schmallenberg, Germany
I am interested in unraveling the molecular mechanisms involved in the establishment of latent viral reservoirs, as well as in those that lead to the escape from latency. Latent reservoirs, established within days following acute HIV infection are continuously repopulated trough-out the course of active viral replication, have an extremely long half life and could hardly be cleared even after 50 years of antiviral therapy {Williams, 2007 #39}. Among mechanisms proposed to contribute to the establishment of viral latency are repressive chromatin environment, the lack of action of key host factors and a failure of viral Tat transactivator protein to act {Richman, 2009 #56}.
We have been focusing our research on the role of chromatin in regulation of HIV-1 gene expression. The property of viral Tat protein to recruit histone acetyltransferase (HAT) p300 to the viral promoter {Marzio, 1998 #40} served as a basis for the studies of epigenetic changes at the viral promoter in the course of reactivation from latency {Lusic, 2003 #15}. We have contributed to describing the recruitment to the integrated viral promoter of a truncated form of STAT5 protein that exerts a repressive role on viral transcription {Crotti, 2007 #28}. By exploring the same model of viral latency we have described the presence along the silent viral genome of a posttranslationally modified kinase component of P-TEFb (CDK9), one of the most important cellular transcriptional partners of HIV-1 {Sabo, 2008 #55}. Since AcCDK9 resides within the PML nuclear bodies we hypothesized that PML nuclear bodies or some other specific nuclear compartments harbor the silent virus. Moreover, we have recently described that HIV-1 provirus undergoes a peculiar structural change when exiting from latency. This looping structure achieved by juxtaposition of the two LTRs only when the virus is actively transcribing, depends on both the viral sequences and on the neighboring chromatin {Perkins, 2008 #43}.
1. Giulia Della Chiara, Andrea Crotti, Elio Liboi, Mauro Giacca, Guido Poli and Marina Lusic (2011) Negative Regulation of HIV-1 Transcription by a Heterodimeric NF-κB1/p50 and C-Terminally Truncated STAT5 Complex. J Mol Biol July 29, 2011 410/5, part II (in press)
2. Awatef Allouch, Cristina Di Primio, Emanuele Alpi, Marina Lusic, Daniele Arosio, Mauro Giacca and Anna Cereseto (2011) KAP-1 inhibits HIV-1 integration Cell Host Microbe 9 (6): 484-95
3. Lara Manganaro, Marina Lusic*, Maria Ines Gutierrez, Anna Cereseto, Giannino Del Sal and Mauro Giacca* (2009) Concerted action of cellular JNK and Pin-1 restricts HIV-1 genome integration to activated CD4+ T lymphocytes Nat Medicine Vol 16 (3): 329-323 (* corresponding authors)
4. Dieudonné M, Maiuri P, Biancotto C, Knezevich A, Kula A, Lusic M, Marcello A. (2009) Transcriptional competence of the integrated HIV-1 provirus at the nuclear periphery EMBO J. Vol 28 (15):2231-2243
5. Arianna Sabo'*, Marina Lusic, Anna Cereseto and Mauro Giacca (2008) Acetylation of conserved lysines in the catalytic core of CDK9 regulates kinase activity and subnuclear localization Mol Cell Biol Vol 28 (7) 2201-12
6. Chiara Vardabasso, Lara Manganaro, Marina Lusic, Alessandro Marcello and Mauro Giacca (2008) The histone chaperone protein Nucleosome Assembly Protein-1 (hNAP-1) binds HIV-1 Tat and promotes viral transcription Retrovirology Vol 28:5:8
7. Kelly J. Perkins, Marina Lusic, Ivonne Mitar, Mauro Giacca and Nick J. Proudfoot (2008) Transcription dependent gene looping of the HIV-1 provirus is dictated by recognition of pre-mRNA processing signals. Molecular Cell Vol 29 (1) 56-68
8. Crotti A, Lusic M, Lupo R, Lievens PM, Liboi E, Chiara GD, Tinelli M, Lazzarin A, Patterson BK, Giacca M, Bovolenta C, Poli G. (2007) "Naturally occurring C-terminally truncated STAT5 is a negative regulator of HIV-1 expression" Blood. Vol109(12):5380-9. Epub 2007 Mar 1
Project Title:
Nuclear topology and the control of HIV-1 gene expression
Increasing evidence indicate that gene activation or silencing is often associated with repositioning of a certain locus relative to nuclear compartments and other genomic loci. We have been focusing our attention on the role of chromatin and nuclear topology in the regulation of HIV-1 gene expression. We demonstrated recently that while transcribing HIV-1 provirus undergoes a peculiar structural change called a gene loop. We have also demonstated that both members of the P-TEFb complex, fundamental cellular partner of HIV-1, if localized inside PML nuclear bodies, are unable to activate HIV-1 transcription. Nuclear bodies (NBs) and in particular Promyelocytic Leukemia (PML) NBs are involved in the epigenetic control of gene expression (1, 2). The PML protein is a member of tripartite motif (TRIM) protein family, which has a well documented role in antiviral defense, although its function in HIV-1 infection remained elusive.
By 3D-immuno DNA-FISH, we visualized latent HIV-1 proviruses in a close proximity to PML NBs, whereas transcriptional activation induced by TNF-α or phorbol esters (TPA) led to the displacement of PML NBs. PML degradation and NB disruption by a shPML-containing lentiviral vector or by arsenic trioxide led to a strong increase in viral transcription concomitant with the changes in the chromatin at the viral genome, as revealed by ChIP for specific histone marks. We found that PML anchors HIV-1 to facultative heterochromatin and serves as a bridging factor for the specific histone methyltransferase G9a.
Taken together, our results indicate that PML restricts viral gene expression by forming a particular repressive nuclear neighbourhood for HIV-1 silencing. These findings can have importance for the development of new therapeutical approaches aimed at the eradication of HIV-1 infection.
In a parallel project, we are also exploring the role of nuclear topology in HIV-1 integration, by combining the data obtained by infections of primary CD4+ lymphocytes and the literature data concerning the hot spots of viral integration.