The Role of Tumor Suppressor p53 Protein in HIV-Host Cell Interactions.

The virus-host relationship is indispensable for executing successful viral infection. The pathogenesis of HIV is determined by an intricate interaction between the host and the virus for the regulation of HIV infection, thereby influencing various aspects, including the regulation of signaling pathways. High mutation rates and population heterogeneity characterize HIV with consequences for viral pathogenesis and the potential to escape the immune system and anti-viral inhibitors used in therapy.

Mitochondrial matrix-localized p53 participates in degradation of mitochondrial RNAs.

Mitochondrial RNA degradation plays an important role in maintenance of the mitochondria genetic integrity. Mitochondrial localization of p53 was observed in non-stressed and stressed cells. p53, as an RNA-binding protein, exerts 3'→5' exoribonuclease activity.

p53 regulates its own expression by an intrinsic exoribonuclease activity through AU-rich elements.

The onco-suppressor p53 protein plays also an important role in the control of various aspects of health and disease. p53 levels are low in normal cells and elevated under stress conditions. While low levels of p53 promote tumor formation, overactive p53 leads to premature aging and cell death.

Cytoplasmic p53 contributes to the removal of uracils misincorporated by HIV-1 reverse transcriptase.

HIV-1 reverse transcriptase (RT) in the cytoplasm of HIV-infected cells efficiently inserts the non-canonical dUTP into the proviral DNA, and extends the dU-terminated DNA. The misincorporation of dUTP leads to mutagenesis, and uracils can down-regulate viral gene expression. However, uracilation might also protect HIV DNA from auto-integration in the cytoplasm.

Diagnosis of HIV-1 infection: Performance of Xpert Qual and Geenius supplemental assays in fourth generation ELISA-reactive samples.

Background: Architect (AR) and Vidas (VD) fourth generation HIV screening immunoassays, which identify early stages of HIV infections, could have false positive results especially at low signal/cutoff (S/C) AR values. Geenius HIV1/2 (GS) is a specific confirmation line immunoassay that is not highly sensitive to early HIV infections. An HIV-1 RNA assay may better detect such infections.