RESUMO
Successful HIV-1 infection and subsequent replication deeply depend on how the virus usurps the host cell machinery. Identification and functional characterization of these host factors may represent a critical strategy for developing novel anti-HIV-1 therapy. Here, expression cloning with a cDNA expression library identified as an inhibitor of HIV-1 infection, a carboxy-terminally truncated form of human POZ/BTB and AT-hook- containing Zinc finger protein 1 (PATZ1), a transcriptional regulatory factor implicated in development and cancer. Knockdown or knockout of endogenous PATZ1 revealed a supportive role of PATZ1 in HIV-1 infection, but not in transduction with murine leukemia virus-based retroviral vector. More specifically, knockdown or knockout of PATZ1 impaired the viral cDNA synthesis but not the entry process and expression of two PATZ1 isoforms in PATZ1-KO cells restored susceptibility to HIV-1 infection. These results indicate that PATZ1 plays an important role in HIV-1 infection.
Assuntos
HIV-1/genética , Interações Hospedeiro-Patógeno/genética , Fatores de Transcrição Kruppel-Like/genética , Linfócitos/virologia , RNA Viral/genética , Proteínas Repressoras/genética , Animais , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Biblioteca Gênica , Células HEK293 , HIV-1/metabolismo , HIV-1/patogenicidade , Humanos , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Fatores de Transcrição Kruppel-Like/metabolismo , Vírus da Leucemia Murina/genética , Vírus da Leucemia Murina/metabolismo , Linfócitos/patologia , Camundongos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , RNA Viral/biossíntese , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/metabolismo , Transdução de Sinais , Vesiculovirus/genética , Vesiculovirus/metabolismoRESUMO
The mechanical contribution of nucleus in adherent cells to bearing intracellular stresses remains unclear. In this paper, the effects of fluid shear stress on morphology and elastic properties of endothelial nuclei were investigated. The morphological observation suggested that the nuclei in the cytoplasm were being vertically compressed under static conditions, whereas they were elongated and more compressed with a fluid shear stress of 2 Pa (20 dyn/cm2) onto the cell. The elongated nuclei remained the shape even after they were isolated from the cells. The micropipette aspiration technique on the isolated nuclei revealed that the elastic modulus of elongated nuclei, 0.62+/-0.15 kPa (n=13, mean+/-SD), was significantly higher than that of control nuclei, 0.42+/-0.12 kPa (n=11), suggesting that the nuclei remodeled their structure due to the shear stress. Based of these results and a transmission electron microscopy, a possibility of the nucleus as an intracellular compression-bearing organelle was proposed, which will impact interpretation of stress distribution in adherent cells.
