Format

Send to

Choose Destination
Neurosci Lett. 2010 Jul 26;479(2):97-101. doi: 10.1016/j.neulet.2010.05.032. Epub 2010 May 16.

E2F1 localizes predominantly to neuronal cytoplasm and fails to induce expression of its transcriptional targets in human immunodeficiency virus-induced neuronal damage.

Author information

1
Department of Pathology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104-6030, USA.

Abstract

As human immunodeficiency virus (HIV) does not induce neuronal damage by direct infection, the mechanisms of neuronal damage or loss in HIV-associated dementia (HAD) remain unclear. We have shown previously that immunoreactivity of transcription factor, E2F1, increases in neurons, localizing predominantly to the cytoplasm, in HIV-associated pathologies. Here we confirm that E2F1 localization is predominantly cytoplasmic in primary postmitotic neurons in vitro and cortical neurons in vivo. To determine whether E2F1 contributes to neuronal death in HAD via transactivation of target promoters, we assessed the mRNA and protein levels of several classical E2F1 transcriptional targets implicated in cell cycle progression and apoptosis in an in vitro model of HIV-induced neurotoxicity and in cortical autopsy tissue from patients infected with HIV. By Q-PCR, we show that mRNA levels of E2F1 transcriptional targets implicated in cell cycle progression (E2F1, Cyclin A, proliferating cell nuclear antigen (PCNA), and dyhydrofolate reductase (DHFR)) and apoptosis (caspases 3, 8, 9 and p19(ARF)) remain unchanged in an in vitro model of HIV-induced neurotoxicity. Further, we show that protein levels of p19(ARF), Cyclin A, and PCNA are not altered in vitro or in the cortex of patients with HAD. We propose that the predominantly cytoplasmic localization of E2F1 in neurons may account for the lack of E2F1 target transactivation in neurons responding to HIV-induced neurotoxicity.

PMID:
20580656
PMCID:
PMC2902623
DOI:
10.1016/j.neulet.2010.05.032
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center