The transcriptional transactivator Tat selectively regulates viral splicing

HIV-1 gene expression requires both viral and cellular factors to control and coordinate transcription. While the viral factor Tat is known for its transcriptional transactivator properties, we present evidence for an unexpected function of Tat in viral splicing regulation. We used a series of HIV-1 reporter minigenes to demonstrate that Tat’s role in splicing is dependent on the cellular co-transcriptional splicing activators Tat-SF1 and CA150. Surprisingly, we show that this Tat-mediated splicing function is independent from transcriptional activation. In the context of the full-length viral genome, this mechanism promotes an autoregulatory feedback that decreases expression of tat and favors expression of the env-specific mRNA. Our data demonstrate that Tat-mediated regulation of transcription and splicing can be uncoupled and suggest a mechanism for the involvement of specific transcriptional activators in splicing

Assessment on the Application of Facilitated Transport Membranes in Cement Plants for CO2 Capture

Carbon dioxide capture from cement plant flue gas can play an important role in mitigating CO2 emission that lead to climate change. Among all the technologies evaluated, membranes have potential to be one of the most energy-efficient and low-cost CO2 capture option. In this work, a novel membrane technology, Facilitated Transport Membranes (FTMs), is assessed to further reduce energy demand and cost for CO2 capture in a cement plant. A new process that employs FTMs is simulated and applied to a real clinker production plant in Italy (Colacem, Gubbio). The process is then compared with other carbon capture technologies. Results show that the FTM technology can be competitive with other technologies despite the need of steam to operate the membrane. Despite the benefit in terms of specific emission compared to more established absorption with liquid amines process, further improvements on membrane performances are needed to gain also an economic advantage for carbon capture in the cement industry

Pericardium of the frog, Rana esculenta, is morphologically designed as a lymphatic space

The importance of the pericardium and the pericardial fluid (PF) in the control of cardiac function has emerged over the past few years. Despite the acknowledgment that amphibians are exposed to both dehydration and excessive water accumulation, nothing is known about their pericardial structure and the morphological basis of the PF formation. We have studied the parietal pericardium (PP) morphology in Rana esculenta by electron microscopy. SEM images of the inner surface, which lines the pericardial cavity, revealed the presence of large vesicles and many small circular openings. TEM observations showed that the PP is made up of an inner mesothelial lining, often constituted by two layers of very flat cells lying on a basal membrane and of regularly oriented collagen bundles. The PP outer surface is lined by a layer of flat cells, without a basal membrane. The mesothelial cells had overlapping boundaries with complex intercellular connections and a rich pool of caveolae opened in the direction of both the pericardial cavity and intercellular spaces. These cells indicate an intense intracellular and/or intercellular transfer of fluids and substances. The intraperitoneal injection of the idromineral hormone, Val5-ANG II, induced PP modifications, particularly evident at the level of the structures involved in the transmesothelial traffic. These lymphatic-like traits suggest that the frog PP represents a large lymphatic sac, subject to paracrine-endocrine remodeling, which can actively adjust the PF, influencing the composition and volume of the myocardial interstitial fluid. © 2003 Wiley-Liss, Inc

Preparation of imido pentamethylcyclopentadienyl molybdenum(IV) complexes. X-ray molecular structure of cis-[MoCp*CI(η-NtBu)]2·C6H6

The reduction of [MoCp * Cl2(NtBu)] 1 with 1 equiv. of 10% sodium amalgam in the presence of CN(2,6-Me2C6H3) yields the green crystalline compound [MoCp * Cl(NtBuCN(2,6-Me2C6H3)] 2 which can be alkylated by MgClMe to give [MoCp * Me(NtBu)CN(2,6-Me2C6H3)] 3. The same reduction in the absence of ligands leads to an almost equimolar mixture of compounds identified as cis- and trans-[MoCp* (μ-Cl)(NtBu)]24 which are slowly and irreversibly transformed into cis-[MoCp * Cl(μ-NtBu)]25 by heating a toluene solution at 90°C. Compounds (cis + trans)-4 and cis-5 are alkylated by MgClMe leading to the same final methyl derivative [MoCp * Me(μ-NtBu)]26, and react with ethylene to yield the adduct [MoCp * Cl(NtBu)(C2H4)] 7. All new complexes were characterized by their analytical composition, IR and NMR spectroscopy and mass spectrometry, and the structure of the benzene solvate of cis-[MoCp * Cl(μ-NtBu)]25 was determined by X-ray diffraction methods.Italian Consiglio Nazionale delle Ricerch

CREB Targets Define the Gene Expression Signature of Malignancies Having Reduced Levels of the Tumor Suppressor Tristetraprolin

The RNA-binding protein Tristetraprolin (TTP, ZFP36) functions as a tumor suppressor that impairs the development and disables the maintenance of MYC-driven lymphoma. In addition, other human cancers expressed reduced levels of TTP, suggesting that it may function as a tumor suppressor in several malignancies. To identify genes that may be associated with TTP tumor suppressor functions in human cancer, we analyzed The Cancer Genome Atlas (TCGA) breast cancer, lung adenocarcinoma, lung squamous cell carcinoma, and colon adenocarcinoma datasets. These analyses defined a signature of 50 genes differentially regulated between high and low TTP-expressing tumors. Notably, patients with low TTP-expressing breast cancer and lung adenocarcinoma had decreased survival rates and more aggressive tumors with increased necrosis. In addition, analysis across non-TCGA tumor gene expression databases identified a broad spectrum of human cancers having similarities with the TTP-low tumor gene signature, including pancreatic, bladder, and prostate cancer. TTP has documented roles in regulating mRNAs encoding inflammatory proteins, and pathway analysis identified several inflammatory pathways that are altered in tumors with low TTP expression. Surprisingly, the TTP-low tumor gene signature includes a core component of 20 under-expressed CREB target genes, suggesting that the regulation of CREB activity may be related to the tumor suppressor function of TTP. Thus, reduced levels of TTP are a potential biomarker for human cancers with poor outcome, and targeting the CREB pathway may be a therapeutic route for treating aggressive TTP-low tumors

Cyclopentadienyl dithiocarbamate and dithiophosphate molybdenum and tungsten complexes

Reactions of [MCp*Cl4] (M=Mo, W; Cp*=η5-C5Me5) with salts of the N,N-diethyldithiocarbamate [Et2dtc]− and O,O′-diethyldithiophosphate [Et2dtp]− anions yield the paramagnetic metal(V) complexes [MCp*Cl3(Et2dtc)] (M=Mo, W) and [MCp*Cl3(Et2dtp)] (M=Mo, W), respectively. Hydrolytic oxidation of both dithiocarbamate–molybdenum complexes with aqueous hydrogen peroxide leads to η2-coordinated peroxo compounds [MoCp*Cl(O–O)O], which were also obtained from [MoCp*Cl4]. The related complexes [MCp′Cl(O–O)O] (M=Mo, Cp′=η5-C5H5; M=W, Cp′=η5-C5Me5) were isolated in a similar way. Reduction of a THF solution of [MoCp*Cl4] with one equivalent of 10% Na/Hg followed by the addition of one equivalent of ammonium dithiophosphate gives [MoCp*Cl2(Et2dtp)] which was also obtained via the reaction of [MoCp*Cl3(Et2dtp)] with MeMgCl, whereas reduction with three equivalents of Na/Hg in the presence of CNtBu leads to the molybdenum(II) complex [MoCp*(Et2dtp)(CNtBu)2] in high yield. All these compounds were characterized by elemental analysis, IR, 1H- and 13C-NMR spectroscopy, magnetic susceptibility measurements and the molecular structures of [Mo(η5-C5H5)Cl(O–O)O] and [Mo(η5–C5Me5)Cl3{η2-S2P(OEt)2}] were determined by X-ray diffraction studies.Consiglio Nazionale delle Ricerche (Rome

Safe and sustainable by design chemicals and materials. Framework for the definition of criteria and evaluation procedure for chemicals and materials

The EU CSS action plan foresees the development of a framework to define safe and sustainable by design (SSbD) criteria for chemicals and materials. The SSbD is an approach to support the design, development, production and use of chemicals and materials that focuses on providing a desirable function (or service), while avoiding or minimising harmful impacts to human health and the environment. The SSbD concept integrates aspects for the domain of safety, circularity and functionality of chemicals and materials, with sustainability consideration throughout their lifecycle, minimising their environmental footprint. SSbD aims at facilitating the industrial transition towards a safe, zero pollution, climate-neutral and resource-efficient economy, addressing adverse effects on humans, ecosystems and biodiversity from a lifecycle perspective. To fulfil these ambitions, there is the need to develop a new framework for the definition of safe and sustainable by design criteria for chemicals and materials. To do so, several frameworks were reviewed including initiatives from research, industry, governmental agencies and NGOs. Capitalising on this information, a framework was developed and is presented in this report including a methodology for the definition of possible SSbD criteria and implementation mechanisms

cAMP/CREB-regulated LINC00473 marks LKB1-inactivated lung cancer and mediates tumor growth

The LKB1 tumor suppressor gene is frequently mutated and inactivated in non–small cell lung cancer (NSCLC). Loss of LKB1 promotes cancer progression and influences therapeutic responses in preclinical studies; however, specific targeted therapies for lung cancer with LKB1 inactivation are currently unavailable. Here, we have identified a long noncoding RNA (lncRNA) signature that is associated with the loss of LKB1 function. We discovered that LINC00473 is consistently the most highly induced gene in LKB1-inactivated human primary NSCLC samples and derived cell lines. Elevated LINC00473 expression correlated with poor prognosis, and sustained LINC00473 expression was required for the growth and survival of LKB1-inactivated NSCLC cells. Mechanistically, LINC00473 was induced by LKB1 inactivation and subsequent cyclic AMP–responsive element–binding protein (CREB)/CREB-regulated transcription coactivator (CRTC) activation. We determined that LINC00473 is a nuclear lncRNA and interacts with NONO, a component of the cAMP signaling pathway, thereby facilitating CRTC/CREB-mediated transcription. Collectively, our study demonstrates that LINC00473 expression potentially serves as a robust biomarker for tumor LKB1 functional status that can be integrated into clinical trials for patient selection and treatment evaluation, and implicates LINC00473 as a therapeutic target for LKB1-inactivated NSCLC

Fluorophore-NanoLuc BRET Reporters Enable Sensitive In Vivo Optical Imaging and Flow Cytometry for Monitoring Tumorigenesis

Fluorescent proteins are widely used to study molecular and cellular events, yet this traditionally relies on delivery of excitation light, which can trigger autofluorescence, photoxicity, and photobleaching, impairing their use in vivo. Accordingly, chemiluminescent light sources such as those generated by luciferases have emerged, as they do not require excitation light. However, current luciferase reporters lack the brightness needed to visualize events in deep tissues. We report the creation of chimeric eGFP-NanoLuc (GpNLuc) and LSSmOrange-NanoLuc (OgNLuc) fusion reporter proteins coined LumiFluors, which combine the benefits of eGFP or LSSmOrange fluorescent proteins with the bright, glow-type bioluminescent light generated by an enhanced small luciferase subunit (NanoLuc) of the deep sea shrimp Oplophorus gracilirostris. The intramolecular bioluminescence resonance energy transfer (BRET) that occurs between NanoLuc and the fused fluorophore generates the brightest bioluminescent signal known to date, including improved intensity, sensitivity and durable spectral properties, thereby dramatically reducing image acquisition times and permitting highly sensitive in vivo imaging. Notably, the self-illuminating and bi-functional nature of these LumiFluor reporters enables greatly improved spatio-temporal monitoring of very small numbers of tumor cells via in vivo optical imaging and also allows the isolation and analyses of single cells by flow cytometry. Thus, LumiFluor reporters are inexpensive, robust, non-invasive tools that allow for markedly improved in vivo optical imaging of tumorigenic processes