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1.
PLoS One ; 15(6): e0234857, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32559215

RESUMO

The Lipocalin Apolipoprotein D (ApoD) is one of the few genes consistently overexpressed in the aging brain, and in most neurodegenerative and psychiatric diseases. Its functions include metabolism regulation, myelin management, neuroprotection, and longevity regulation. Knowledge of endogenous regulatory mechanisms controlling brain disease-triggered ApoD expression is relevant if we want to boost pharmacologically its neuroprotecting potential. In addition to classical transcriptional control, Lipocalins have a remarkable variability in mRNA 5'UTR-dependent translation efficiency. Using bioinformatic analyses, we uncover strong selective pressures preserving ApoD 5'UTR properties, indicating unexpected functional conservation. PCR amplifications demonstrate the production of five 5'UTR variants (A-E) in mouse ApoD, with diverse expression levels across tissues and developmental stages. Importantly, Variant E is specifically expressed in the oxidative stress-challenged brain. Predictive analyses of 5'UTR secondary structures and enrichment in elements restraining translation, point to Variant E as a tight regulator of ApoD expression. We find two genomic regions conserved in human and mouse ApoD: a canonical (α) promoter region and a previously unknown region upstream of Variant E that could function as an alternative mouse promoter (ß). Luciferase assays demonstrate that both α and ß promoter regions can drive expression in cultured mouse astrocytes, and that Promoter ß activity responds proportionally to incremental doses of the oxidative stress generator Paraquat. We postulate that Promoter ß works in association with Variant E 5'UTR as a regulatory tandem that organizes ApoD gene expression in the nervous system in response to oxidative stress, the most common factor in aging and neurodegeneration.


Assuntos
Regiões 5' não Traduzidas , Apolipoproteínas D/genética , Apolipoproteínas E/genética , Regiões Promotoras Genéticas , Animais , Apolipoproteínas D/metabolismo , Apolipoproteínas E/metabolismo , Astrócitos/metabolismo , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Linhagem Celular , Herbicidas/toxicidade , Lipocalinas/genética , Lipocalinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Estresse Oxidativo , Paraquat/toxicidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
PLoS One ; 14(3): e0213206, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30840684

RESUMO

The Lipocalin family is a group of homologous proteins characterized by its big array of functional capabilities. As extracellular proteins, they can bind small hydrophobic ligands through a well-conserved ß-barrel folding. Lipocalins evolutionary history sprawls across many different taxa and shows great divergence even within chordates. This variability is also found in their heterogeneous tissue expression pattern. Although a handful of promoter regions have been previously described, studies on UTR regulatory roles in Lipocalin gene expression are scarce. Here we report a comprehensive bioinformatic analysis showing that complex post-transcriptional regulation exists in Lipocalin genes, as suggested by the presence of alternative UTRs with substantial sequence conservation in mammals, alongside a high diversity of transcription start sites and alternative promoters. Strong selective pressure could have operated upon Lipocalins UTRs, leading to an enrichment in particular sequence motifs that limit the choice of secondary structures. Mapping these regulatory features to the expression pattern of early and late diverging Lipocalins suggests that UTRs represent an additional phylogenetic signal, which may help to uncover how functional pleiotropy originated within the Lipocalin family.


Assuntos
Simulação por Computador , Evolução Molecular , Lipocalinas/genética , Proteínas/metabolismo , Processamento Pós-Transcricional do RNA , Regiões não Traduzidas/genética , Animais , Biologia Computacional , Humanos , Lipocalinas/metabolismo , Mamíferos , Filogenia , Proteínas/genética , Sítio de Iniciação de Transcrição
3.
Sensors (Basel) ; 17(1)2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28067801

RESUMO

There are several specific solutions for accessing sensors and actuators present in any process or system through a TCP/IP network, either local or a wide area type like the Internet. The usage of sensors and actuators of different nature and diverse interfaces (SPI, I2C, analogue, etc.) makes access to them from a network in a homogeneous and secure way more complex. A framework, including both software and hardware resources, is necessary to simplify and unify networked access to these devices. In this paper, a set of open-source software tools, specifically designed to cover the different issues concerning the access to sensors and actuators, and two proposed low-cost hardware architectures to operate with the abovementioned software tools are presented. They allow integrated and easy access to local or remote sensors and actuators. The software tools, integrated in the free authoring tool Easy Java and Javascript Simulations (EJS) solve the interaction issues between the subsystem that integrates sensors and actuators into the network, called convergence subsystem in this paper, and the Human Machine Interface (HMI)-this one designed using the intuitive graphical system of EJS-located on the user's computer. The proposed hardware architectures and software tools are described and experimental implementations with the proposed tools are presented.

4.
Sensors (Basel) ; 16(11)2016 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-27809229

RESUMO

In this paper the design and implementation of a network for integrating Programmable Logic Controllers (PLC), the Object-Linking and Embedding for Process Control protocol (OPC) and the open-source Easy Java Simulations (EJS) package is presented. A LabVIEW interface and the Java-Internet-LabVIEW (JIL) server complete the scheme for data exchange. This configuration allows the user to remotely interact with the PLC. Such integration can be considered a novelty in scientific literature for remote control and sensor data acquisition of industrial plants. An experimental application devoted to remote laboratories is developed to demonstrate the feasibility and benefits of the proposed approach. The experiment to be conducted is the parameterization and supervision of a fuzzy controller of a DC servomotor. The graphical user interface has been developed with EJS and the fuzzy control is carried out by our own PLC. In fact, the distinctive features of the proposed novel network application are the integration of the OPC protocol to share information with the PLC and the application under control. The user can perform the tuning of the controller parameters online and observe in real time the effect on the servomotor behavior. The target group is engineering remote users, specifically in control- and automation-related tasks. The proposed architecture system is described and experimental results are presented.

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