Project description:Studies have shown that HIV-infected patients develop neurocognitive disorders characterized by neuronal dysfunction. The lack of productive infection of neurons by HIV suggests that viral and cellular proteins, with neurotoxic activities, released from HIV-1-infected target cells can cause this neuronal deregulation. The viral protein R (Vpr), a protein encoded by HIV-1, has been shown to alter the expression of various important cytokines and inflammatory proteins in infected and uninfected cells; however the mechanisms involved remain unclear. Using a human neuronal cell line, we found that Vpr can be taken up by neurons causing: (i) deregulation of calcium homeostasis, (ii) endoplasmic reticulum-calcium release, (iii) activation of the oxidative stress pathway, (iv) mitochondrial dysfunction and v- synaptic retraction. In search for the cellular factors involved, we performed microRNAs and gene array assays using human neurons (primary cultures or cell line, SH-SY5Y) that we treated with recombinant Vpr proteins. Interestingly, Vpr deregulates the levels of several microRNAs (e.g. miR-34a) and their target genes (e.g. CREB), which could lead to neuronal dysfunctions. Therefore, we conclude that Vpr plays a major role in neuronal dysfunction through deregulating microRNAs and their target genes, a phenomenon that could lead to the development of neurocognitive disorders. Human fetal neurons were chosen to examine the impact of HIV-1 Vpr protein on gene expression
Project description:Studies have shown that HIV-infected patients develop neurocognitive disorders characterized by neuronal dysfunction. The lack of productive infection of neurons by HIV suggests that viral and cellular proteins, with neurotoxic activities, released from HIV-1-infected target cells can cause this neuronal deregulation. The viral protein R (Vpr), a protein encoded by HIV-1, has been shown to alter the expression of various important cytokines and inflammatory proteins in infected and uninfected cells; however the mechanisms involved remain unclear. Using a human neuronal cell line, we found that Vpr can be taken up by neurons causing: (i) deregulation of calcium homeostasis, (ii) endoplasmic reticulum-calcium release, (iii) activation of the oxidative stress pathway, (iv) mitochondrial dysfunction and v- synaptic retraction. In search for the cellular factors involved, we performed microRNAs and gene array assays using human neurons (primary cultures or cell line, SH-SY5Y) that we treated with recombinant Vpr proteins. Interestingly, Vpr deregulates the levels of several microRNAs (e.g. miR-34a) and their target genes (e.g. CREB), which could lead to neuronal dysfunctions. Therefore, we conclude that Vpr plays a major role in neuronal dysfunction through deregulating microRNAs and their target genes, a phenomenon that could lead to the development of neurocognitive disorders. Human neurons SH-SY5Y were chosen to examine the impact of HIV-1 Vpr protein on gene expression
Project description:Studies have shown that HIV-infected patients develop neurocognitive disorders characterized by neuronal dysfunction. The lack of productive infection of neurons by HIV suggests that viral and cellular proteins, with neurotoxic activities, released from HIV-1-infected target cells can cause this neuronal deregulation. The viral protein R (Vpr), a protein encoded by HIV-1, has been shown to alter the expression of various important cytokines and inflammatory proteins in infected and uninfected cells; however the mechanisms involved remain unclear. Using a human neuronal cell line, we found that Vpr can be taken up by neurons causing: (i) deregulation of calcium homeostasis, (ii) endoplasmic reticulum-calcium release, (iii) activation of the oxidative stress pathway, (iv) mitochondrial dysfunction and v- synaptic retraction. In search for the cellular factors involved, we performed microRNAs and gene array assays using human neurons (primary cultures or cell line, SH-SY5Y) that we treated with recombinant Vpr proteins. Interestingly, Vpr deregulates the levels of several microRNAs (e.g. miR-34a) and their target genes (e.g. CREB), which could lead to neuronal dysfunctions. Therefore, we conclude that Vpr plays a major role in neuronal dysfunction through deregulating microRNAs and their target genes, a phenomenon that could lead to the development of neurocognitive disorders. Using primary cultures and neuronal cell lines, we examined the impact of a viral protein (HIV-1 Vpr) on the expression of miRNAs and mRNAs.
Project description:Studies have shown that HIV-infected patients develop neurocognitive disorders characterized by neuronal dysfunction. The lack of productive infection of neurons by HIV suggests that viral and cellular proteins, with neurotoxic activities, released from HIV-1-infected target cells can cause this neuronal deregulation. The viral protein R (Vpr), a protein encoded by HIV-1, has been shown to alter the expression of various important cytokines and inflammatory proteins in infected and uninfected cells; however the mechanisms involved remain unclear. Using a human neuronal cell line, we found that Vpr can be taken up by neurons causing: (i) deregulation of calcium homeostasis, (ii) endoplasmic reticulum-calcium release, (iii) activation of the oxidative stress pathway, (iv) mitochondrial dysfunction and v- synaptic retraction. In search for the cellular factors involved, we performed microRNAs and gene array assays using human neurons (primary cultures or cell line, SH-SY5Y) that we treated with recombinant Vpr proteins. Interestingly, Vpr deregulates the levels of several microRNAs (e.g. miR-34a) and their target genes (e.g. CREB), which could lead to neuronal dysfunctions. Therefore, we conclude that Vpr plays a major role in neuronal dysfunction through deregulating microRNAs and their target genes, a phenomenon that could lead to the development of neurocognitive disorders.
Project description:HIV-1 Vpr protein is a multifunctional protein which perturbs human transcriptome and interacts with a number of cellular proteins. In this study, we have attempted to explore the efffects of Vpr on human transcriptome and have identified several genes which are involved in innate immune responses. We used the microarray analysis to elucidate the differnetail expression pattern of differnet genes in human dendritic cells infected with HIV-1 Vpr. As result we found that HIV-1 Vpr protein leads to the induction of various interferon stimualted genes (ISGs) in human monocyte derived dendritic cells. Human monocytes-derived dendritic cells (MDDCs) were isolated from peripheral blood mononuclear cells (PBMCs) from two healthy donors and were infected with recombinant adenoviruses either expressing HIV-1 Vpr or ZsGreen1 as a control. At 48 hours post-infection, RNA was isolated and subjected to microarray analysis.
Project description:HIV-1 Vpr protein is a multifunctional protein which perturbs human transcriptome and interacts with a number of cellular proteins. In this study, we have attempted to explore the efffects of Vpr on human transcriptome and have identified several genes which are involved in innate immune respone and cell signaling pathways. We used the microarray analysis to elucidate the differnetail expression pattern of differnet genes in human macrophages infected with HIV-1 Vpr. As result we found that HIV-1 Vpr protein leads to the induction of various interferon stimualted genes (ISGs) and chemokines in human macrophages. Human monocytes-derived macrophages (MDMs) were isolated from peripheral blood mononuclear cells (PBMCs) from two healthy donors and were infected with recombinant adenoviruses either expressing HIV-1 Vpr or ZsGreen1 as a control. At 48 hours post-infection, RNA was isolated and subjected to microarray analysis.
Project description:HIV-1 Vpr protein is a multifunctional protein which perturbs human transcriptome and interacts with a number of cellular proteins. In this study, we have attempted to explore the efffects of Vpr on human transcriptome and have identified several genes which are involved in innate immune responses. We used the microarray analysis to elucidate the differnetail expression pattern of differnet genes in human dendritic cells infected with HIV-1 Vpr. As result we found that HIV-1 Vpr protein leads to the induction of various interferon stimualted genes (ISGs) in human monocyte derived dendritic cells.
Project description:HIV-1 Vpr protein is a multifunctional protein which perturbs human transcriptome and interacts with a number of cellular proteins. In this study, we have attempted to explore the efffects of Vpr on human transcriptome and have identified several genes which are involved in innate immune respone and cell signaling pathways. We used the microarray analysis to elucidate the differnetail expression pattern of differnet genes in human macrophages infected with HIV-1 Vpr. As result we found that HIV-1 Vpr protein leads to the induction of various interferon stimualted genes (ISGs) and chemokines in human macrophages.
Project description:HIV-1 accessory protein, Vpr, is required for efficient HIV-1 infection of macrophages. Here we show that Vpr reprograms macrophage gene expression by altering the activity of master transcriptional regulator, PU.1, which is responsible for regulating the expression of host immune response genes and is necessary for normal hematopoiesis. In HIV-infected primary macrophages, Vpr-dependent changes in PU.1 levels result in suppression of known anti-viral targets of Vpr including IFITM3 and MRC1. Moreover, we find that PU.1 and its co-factor TET2 are co-recruited to DCAF1 by Vpr and targeted for accelerated degradation. Downmodulation of PU.1 is a highly conserved function of Vpr that is maintained across primate lentiviruses including HIV-2 and several SIVs. In contrast, this activity is not shared by the evolutionarily related accessory protein Vpx. Our findings demonstrate how Vpr dramatically enhances HIV spread in macrophages by targeting a myeloid-specific transcription factor needed for expression of multiple viral restriction factors.
Project description:Finding the differences in gene expression in three regions of the brai, basal ganglia, white matter, and frontal cortex, in normal, HIV infected, HIV inefected with neurocognitive impairment, and HIV infected with both neurocognitive impairment and encephalitis patients. We used microarrays to identify differentially expressed genes in normal, HIV infected, HIV inefected with neurocognitive impairment, and HIV infected with both neurocognitive impairment and encephalitis patients. Samples from three different brain regions from normal, HIV infected, HIV infected with neurocognitive impairment (HAD: HIV-associated dementia), and HIV infected with both neurocognitive impairment and encephalitis (HIVE: HIV encephalitis) patients were collected for RNA isolation and supsequent Affymetrix microarray analysis. We sought to obtain gene expression levels in different brain regions to find implication of HIV and the neurological impairment and inflammation associated with HIV infection.