Date of Award

2011-01-01

Degree Name

Master of Science

Department

Biological Sciences

Advisor(s)

Dr. Manuel Llano

Abstract

Poly (ADP-ribose) polymerase-1 (PARP-1) is a cellular enzyme involved in genome stability and transcriptional regulation. The role of this protein in HIV-1 infection is largely controversial. Some reports indicated a fundamental role of PARP-1 in HIV-1 DNA integration and results from other laboratories do not support these conclusions. An important characteristic in all these experiments is that the HIV-1 target cells that were used express, in addition to PARP-1, the functional homologue PARP-2. We evaluated the role of PARP-1 in the chicken B lymphoblastoid cell line DT40. These cells naturally lack PARP-2 and support the early steps of HIV infection. We have observed that DT40 PARP-1 -/- cells was significantly more susceptible to infection with HIV- and murine leukemia virus (MLV)-derived viral vectors than their wild type counterpart. Expression of human PARP-1 in DT40 PARP-1 -/- cells decreased retroviral susceptibility to wild type levels, while expression of human PARP-2 has only a partial effect. Analysis of the retroviral life cycle by real time PCR indicated that levels of retroviral provirus were similar in DT40 wild type, PARP-1 -/-, and PARP-1 -/- cells expressing human PARP-1. These results, suggested that retroviral latency was established in cells expressing PARP-1. Treatment of HIV- or MLV-infected cells with the histone deacetylase inhibitor sodium butyrate or the DNA methyl transferase 1 inhibitor 5-azacytidine suppressed the differences in retroviral transgene expression observed in cells expressing or not PARP-1.

Language

en

Provenance

Received from ProQuest

File Size

39 pages

File Format

application/pdf

Rights Holder

Daniel Reyes

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