15 research outputs found
Assessment of genetic variation for the LINE-1 retrotransposon from next generation sequence data
<p>Abstract</p> <p>Background</p> <p>In humans, copies of the Long Interspersed Nuclear Element 1 (LINE-1) retrotransposon comprise 21% of the reference genome, and have been shown to modulate expression and produce novel splice isoforms of transcripts from genes that span or neighbor the LINE-1 insertion site.</p> <p>Results</p> <p>In this work, newly released pilot data from the 1000 Genomes Project is analyzed to detect previously unreported full length insertions of the retrotransposon LINE-1. By direct analysis of the sequence data, we have identified 22 previously unreported LINE-1 insertion sites within the sequence data reported for a mother/father/daughter trio.</p> <p>Conclusions</p> <p>It is demonstrated here that next generation sequencing data, as well as emerging high quality datasets from individual genome projects allow us to assess the amount of heterogeneity with respect to the LINE-1 retrotransposon amongst humans, and provide us with a wealth of testable hypotheses as to the impact that this diversity may have on the health of individuals and populations.</p
Albumin-Like Proteins Are Critical Regulators of Vascular Redox Signaling
This laboratory previously identified an albumin-like protein (denoted as p70) as a component of the macromolecular complex assembled within the 5 -regulatory region of redox-sensitive genes in vascular smooth muscle cells (vSMCs). Here we show that p70 is present in the cytosolic and nuclear compartments of vSMCs and dynamically responsive to redox status. Intense cytoplasmic and perinuclear staining, coupled with enhanced nuclear localization, was observed in vSMCs, but not HepG2 cells, treated with benzo(a)pyrene (BaP), H 2 O 2 , or N-acetylcysteine, agents known to modulate redox status. 3 RACE indicated that p70 is not generated as a product of endogenous gene expression, but rather taken up from the extracellular compartment. While p70 was undetectable in cells grown for 24 hours under serum-free conditions, cell-associated, acid-resistant albumin was detected 30 min after the addition of exogenous albumin. vSMCs incubated at 4 ∘ C with 100 g/mL unlabeled BSA and 10 g/mL FITC-BSA for 60 minutes and switched to 37 ∘ C to examine temperature-sensitive label uptake showed punctate structures throughout the cell consistent with albumin internalization at the higher temperature. Albumin was found to influence redox-signaling, as evidenced by modulation of cyp1a1 gsta1 and Ha-ras gene inducibility. Together, these results implicate albumin and albumin-like proteins as critical regulators of vascular redox signaling
Hepatocyte-specific mitogen-activated protein kinase phosphatase 1 in sexual dimorphism and susceptibility to alcohol induced liver injury
BackgroundIt is well established that females are more susceptible to the toxic effects of alcohol, although the exact mechanisms are still poorly understood. Previous studies noted that alcohol reduces the expression of mitogen-activated protein kinase phosphatase 1 (MKP1), a negative regulator of mitogen-activated protein kinases (MAPK) in the liver. However, the role of hepatocyte- specific MKP1 in the pathogenesis of alcohol-associated liver disease (ALD) remains uncharacterized. This study aimed to evaluate the role of hepatocyte-specific MKP1 in the susceptibility and sexual dimorphism in alcohol-induced liver injury.MethodsC57Bl/6 mice were used in an intragastric ethanol feeding model of alcohol-associated steatohepatitis (ASH). Hepatocyte-specific Mkp1-/- knockout and (Mkp1+/+ “f/f” male and female mice were subjected to the NIAAA chronic plus binge model. Primary mouse hepatocytes were used for in vitro studies. Liver RNA sequencing was performed on an Illumina NextSeq 500. Liver injury was evaluated by plasma alanine transaminase (ALT), hepatic ER stress and inflammation markers. Statistical analysis was carried out using ANOVA and the unpaired Student’s t-test.ResultsASH was associated with the severe injury accompanied by increased endoplasmic reticulum (ER) stress and significant downregulation of Dusp1 mRNA expression. In vitro, ethanol treatment resulted in a time-dependent decrease in Dusp1 mRNA and protein expression in primary hepatocytes in both males and females; however, this effect was significantly more pronounced in hepatocytes from females. In vivo, female mice developed more liver injury in a chronic plus binge model which was accompanied by a significant decrease in liver Dusp1 mRNA expression. In comparison, liver Dusp1 was not changed in male mice, while they developed milder injury to alcohol. Mkp1 deletion in hepatocytes led to increased alcohol induced liver injury, ER stress and inflammation in both sexes.ConclusionHepatocyte Mkp1 plays a significant role in alcohol induced liver injury. Alcohol downregulates Mkp1 expression in hepatocytes in a sex dependent manner and could play a role in sexual dimorphism in increased female susceptibility to alcohol
Gfi1 Coordinates Epigenetic Repression of p21(Cip/WAF1) by Recruitment of Histone Lysine Methyltransferase G9a and Histone Deacetylase 1
The growth factor independent 1 (Gfi1) transcriptional regulator oncoprotein plays a crucial role in hematopoietic, inner ear, and pulmonary neuroendocrine cell development and governs cell processes as diverse as self-renewal of hematopoietic stem cells, proliferation, apoptosis, differentiation, cell fate specification, and oncogenesis. However, the molecular basis of its transcriptional functions has remained elusive. Here we show that Gfi1 recruits the histone lysine methyltransferase G9a and the histone deacetylase 1 (HDAC1) in order to modify the chromatin of genes targeted for repression by Gfi1. G9a and HDAC1 are both in a repressive complex assembled by Gfi1. Endogenous Gfi1 colocalizes with G9a, HDAC1, and K9-dimethylated histone H3. Gfi1 associates with G9a and HDAC1 on the promoter of the cell cycle regulator p21(Cip/WAF1), resulting in an increase in K9 dimethylation at histone H3. Silencing of Gfi1 expression in myeloid cells reverses G9a and HDAC1 recruitment to p21(Cip/WAF1) and elevates its expression. These findings highlight the role of epigenetics in the regulation of development and oncogenesis by Gfi1
Protocolo de telemedicina para la consulta psiquiátrica
Colombia had are several isolated populations in areas without access to specialized health services, much less on mental health. Telemedicine is a tool that allows to provide these services, bringing specialized medicine at lower costs and similar quality through information and communication technologies. As a solution to this problem, a psychiatric tele-consultation protocol and the implementation of a web application was proposed in order to provide diagnosis and follow up to patients with mental diseases. For the development of this project; clinical and operational guidelines in Telepsychiatry services were reviewed, diseases of interest were analyzed, a software engineering process was implemented, and finally a clinical and technical evaluation were designed in order to have a feedback for the system.En Colombia existen diversas poblaciones en zonas aisladas que no tienen acceso a servicios de salud especializados, entre ellos salud mental. La telemedicina es una herramienta que permite proporcionar estos servicios, llevando medicina especializada a un menor costo y similar calidad a través de tecnologías de la información y las comunicaciones. Como una solución a esta problemática se propuso la estructuración de un protocolo de teleconsulta psiquiátrica y la implementación de una aplicación web, con el fin de proveer servicios de diagnóstico y control a pacientes con incidencia de enfermedades mentales. Para la realización de este proyecto se analizaron lineamientos clínicos y operacionales en servicios de telepsiquiatría, se realizó un análisis de algunas patologías de interés, se hizo un desarrollo del proceso de ingeniería de software, y por último se diseñó una evaluación técnica y clínica de la aplicación para así obtener una retroalimentación del sistema
Albumin-Like Proteins Are Critical Regulators of Vascular Redox Signaling
This laboratory previously identified an albumin-like protein (denoted as p70) as a component of the macromolecular complex assembled within the 5′-regulatory region of redox-sensitive genes in vascular smooth muscle cells (vSMCs). Here we show that p70 is present in the cytosolic and nuclear compartments of vSMCs and dynamically responsive to redox status. Intense cytoplasmic and perinuclear staining, coupled with enhanced nuclear localization, was observed in vSMCs, but not HepG2 cells, treated with benzo(a)pyrene (BaP), H2O2, or N-acetylcysteine, agents known to modulate redox status. 3′ RACE indicated that p70 is not generated as a product of endogenous gene expression, but rather taken up from the extracellular compartment. While p70 was undetectable in cells grown for 24 hours under serum-free conditions, cell-associated, acid-resistant albumin was detected 30 min after the addition of exogenous albumin. vSMCs incubated at 4°C with 100 μg/mL unlabeled BSA and 10 μg/mL FITC-BSA for 60 minutes and switched to 37°C to examine temperature-sensitive label uptake showed punctate structures throughout the cell consistent with albumin internalization at the higher temperature. Albumin was found to influence redox-signaling, as evidenced by modulation of cyp1a1 gsta1 and Ha-ras gene inducibility. Together, these results implicate albumin and albumin-like proteins as critical regulators of vascular redox signaling